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From Swagger API to HTML tags, HubSpot has compiled definitions for more than 100 terms related to APIs, CSS, HTML, DevOps, Java, and Python in this glossary. 

API Terms

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An API, short for application programming interface, is a series of rules. To be even clearer, it is an information middleman. APIs allow for an application to extract information from a piece of software and use that information in their own application, or sometimes for data analysis.

In the plainest terms, an API is a blueprint that enables "your stuff" to talk to and work with "their stuff." Your stuff, in this case, is known as the API endpoint.

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API Documentation

API documentation is essentially an instruction manual that explains how to use an API and its services. This manual might contain tutorials, code examples, screenshots, and anything else that helps users better understand how to work with the API.

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API Gateway

An API gateway accepts all API calls and then acts as a reverse proxy, retrieving resources from backend applications on behalf of the client application. An API gateway not only accepts API calls — but it also handles tasks related to API services like user authentication, rate limiting, monitoring, and more.

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API Management

API management is the process of building, publishing, administering, and analyzing APIs. It is accomplished through a combination of tools and services to support provisioning, securing, and maintaining APIs. Visibility is key to ensuring APIs are functioning and being consumed as intended.

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API Testing

API testing assesses the functions of application programming interfaces (APIs) directly by validating the logic of these frameworks and ensuring they perform as intended. Existing as the middle layer between databases and the user interface (UI), APIs facilitate communication between disparate functions. Common types of API testing include validation, functional, UI, security, load, runtime and error detection.


cURL stands for "client URL" and is an open-source software tool created by Swedish developer Daniel Stenberg. The tool uses both a command-line tool (curl) and library (libcurl) to transfer data across multiple network protocols. It was originally designed to automatically fetch currency exchange rates. cURL supports HTTPS and can conduct SSL certificate validation when secure protocol transfers are used.

Google API

Google APIs are a set of application programming interfaces developed by Google that facilitate communications with Google Services. These APIs are commonly used to connect third-party applications with Google tools such as Search, Gmail, Maps or Translate. Google APIs offer multiple functions including data analytics, machine learning as a service (MLaaS) and the ability to access user data with permission.


The term idempotent is a combination of idem, Latin for same, and potence, Old French for power. Operations that are idempotent return the same result regardless of how many times they are executed or the circumstances under which this execution occurs. Idempotence can be a property of functions, requests, statements and methods and is tied to the operation itself, not its programming language.

Open API

An open API, also referred to as a public API, is publicly published and freely shared. Once published, an open API can be used by anyone in any way without organization interference.

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A payload is the portion of a transmitted information that contains the actual message or relevant information. In the context of a webpage, the content displayed on-screen is the payload; other elements such as headers and metadata simply facilitate payload delivery. Payload may also refer to the portion of malware or ransomware that carries out the attack on a system.


An SDK, or Software Development Kit, is a set of software-building tools for a specific platform, like Facebook, or a programming language, like Java. This kit includes compilers, runtime environments, documentation, debuggers, and a framework or set of code libraries that are specific to the platform or language. It usually includes an API as well.

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Swagger API

The Swagger API framework is a set of open-source offerings built to help programmers develop, design, document, and use REST APIs. The tool is built around the OpenAPI specification and contains three components: swagger editor, swagger UI, and Swagger Codegen.

CSS Terms

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CSS is a language that defines the design and layout of web pages. In other words, CSS controls how web pages look when loaded in a browser. We call this design and layout the “style” of the page. CSS is the standard language for styling and typically works in conjunction with HTML (the language that defines the content of web pages).

CSS stands for Cascading Style Sheets. “Style Sheets” refers to the CSS document itself, and “Cascading” refers to how style rules are applied to page elements. I’ll explain what that means in more detail later on, but let’s first learn what CSS does.

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The CSS EM unit is used to define font size based on the properties of a parent element. Derived from a typographical unit that used the width of a capital M as the parent element of other typeface elements, the em unit is a relative rather than a static font size. For example, if your font size is 16px, a font of 3em would be 48px.


The CSS REM unit means “root EM” and is used to calculate the size of a font based on the root element of the font size chosen by a user. This allows your site or mobile application to resize text based on user-defined specifications rather than static elements. For example, if a user sets their standard font size at 16px, other elements such as h1, h2, etc. can be defined as percentages of the root font.

RGB Colors

RGB is another color model based on the combination of the primary colors — hence, the shorthand for Red, Green, Blue. RBG color codes are composed of three numbers separated by commas. Each number represents the intensity of the respective primary color as an integer between 0 and 255. These numbers are then wrapped in parentheses and preceded by a lowercase “rgb.”

So rgb (0, 0, 0) is black, rgb (255, 0, 0) is red, and rgb (0, 0, 255) is blue.

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The viewport in CSS refers to the area of a web page visible to the user based on their device. Because the viewport varies based on the device, websites designed for desktops won’t fit smaller mobile tablets or phones. Using the <meta> tag in HTML5 lets designers provide instructions for browsers to scale webpage elements up or down based on the user’s device.

Z Index

The z-index is a property of CSS which determines the “stack level” of an HTML element. Elements with higher z-values are closer to the top of the stack — the user viewpoint — than elements with lower values. For example, natural stacking order on a HTML page sees backgrounds and borders at the bottom of the stack, while inline and positioned elements are at the top. Changing the z-index value can bring these lower-stack elements to the forefront.

DevOps Terms

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Configuration Management

Configuration management is the practice of cataloging and tracking the physical and virtual systems within an organization as well as the metadata for these assets. In software development, configuration management is used to optimize application configurations for their production environments to avoid downtime.

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Containerization is the process of packaging software code together into a single "container" that includes all the components it requires to run, such as operating system libraries and any other dependencies. This approach allows software or applications inside the container to be easily moved and operated in any environment since they exist independent of the underlying infrastructure or operating system.

Continuous Integration

Continuous integration is an approach to development where code changes are regularly merged into a shared repository or branch. The combined codebase is then built into a test application where automated tests are run against it to root out bugs. Any discovered defects are turned back over to the developers to fix.

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Crud Meaning

CRUD stands for “create, read, update, delete”. It’s a simple way to remember the four basic functions that APIs should support, and makes it easy for developers to evaluate API models before putting them into production. While APIs don’t need to support all four functions, they should deliver at least one of the CRUD components; otherwise, they may need to fall under other, larger models.

Data Abstraction

Data abstraction is the process of reducing data volumes by creating a simplified version of the original data which contains only its essential characteristics. Abstraction both reduces total complexity and makes it possible for database designers to create multi-use templates; the nature of abstractions means that their essential elements can be reconfigured to create differing results.


DevOps is an alternative approach to the software development workflow, improving speed, efficiency, and productivity. Integrating two previously siloed roles — development and operations — DevOps also reduces the number of steps in the software lifecycle.

DevOps' focus is to encourage the use of several techniques to improve the workflow — and results of it — for your team. It promotes collaboration, automation, and an iterative approach to managing your software development (Dev) and software operations (Ops).

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Docker Swarm

Docker swarm is a container orchestration tool, which allows users to manage multiple containers across multiple host machines. In a typical docker swarm, at least one manager nodes handles several worker nodes to help manage their resources effectively. While the tool is no longer offered as-a-service, is remains part of docker-ce and it still used to help orchestrate containers at scale.


Encapsulation is the practice of bundling data with the methods used to perform operations on that data. It may also be used to restrict access to data within an object — such as PII or financial data — thus allowing the function to be maintained without compromising security. Encapsulation also facilities the easy transfer of functions or operations within a data bundle.

Front End Development

Front-end development is the process of creating user-facing elements of a website or application. Also called client-side development, front-end functions leverage solutions such as HTML, JavaScript, and CSS to ensure that websites and applications deliver a consistent experience across platforms and devices. The ongoing evolution of tools and technologies in this field requires developers to continually monitor and update sites and apps as required.


A full-stack developer is one who works on the front end (the interface) and back end (the inner workings) of a website or web application. Full-stack developers possess a comprehensive understanding of the technologies that make up a web-based system. They can help effectively plan, execute, and troubleshoot web-based projects with their extensive knowledge.

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Logs are text files where applications and operating systems write events. These logs allow IT professionals to view the history of events leading up to an issue or anomaly, in turn helping them pinpoint its origin. Effective log management is critical for DevOps teams to create applications at speed while reducing the risk of errors and issues. They’re also used to assess and improve overall system performance.

Object-Oriented Programming

Object-oriented programming (OOP) is an approach to coding that focuses on creating small pieces of reusable code — called classes — that are made up of individual objects. Where classes are broader categories, such as “car”, objects might refer to specific car makes or models. Languages such as JavaScript, C++, Java, and Python are OOP languages.


Polymorphism is the ability of a variable, object, or function to take on multiple forms in object-oriented programming (OOP). In programming languages that support polymorphism, class objects that have the same parent class in a hierarchical tree can have functions with the same name but that exhibit different behaviors. For example, the parent “shape” class may contain class objects such as triangle, oval and square, each of which are subsets of shape but produce different draw functions.


TaaS stands for testing-as-a-service and is a cloud-based approach to software testing. Much like SaaS, PaaS and other as-a-service offerings, TaaS makes it possible to outsourcing testing operations. Testing functions are then accessed via a cloud-connected web interface that provides access to on-demand, self-service testing frameworks, or may be part of a larger managed service offering that sees testing performed as specified by clients.

HTML Terms

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A Href

In HTML, the inline a (anchor) element denotes a hyperlink from one web address to another. All functional a elements must contain the href (hypertext reference) attribute inside the opening a tag. The href attribute indicates the destination of the hyperlink. Without the href attribute, the a element won’t work.

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An HTML attribute is an additional characteristic or property of an HTML element that is specified in the start tag or the element itself. These attributes typically take the form of name/value pairs that define specific characteristics such as the width and height of an image. For example, <img> tags must contain both a source <src> and alternative description <alt> attribute.

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Block Element

A block element in HTML is one of two default display values for elements — the other value element is inline. Block elements always start on a new line, and browsers will automatically add margins before and after the element. You don’t need to specify if an element is block or inline; for example, elements such as <p> and <div> are always displayed as block elements.


The HTML canvas element is a container for graphics created in JavaScript, and is used to display these graphics on a webpage. Incorporating the <canvas> element into you webpage makes it possible to draw graphics such boxes, paths, circles, texts, and paths on-demand. Worth noting? Canvas is only used to replicate the graphics from JavaScript onto your webpage; the drawings themselves must be created in JavaScript first.

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File Path

An HTML file path indicates the location of a file within a folder structure and helps web browsers easily access files that link to external resources such as images, videos, and style sheets. File paths must include a source element that browsers can follow. There are two types of file paths: Absolute and relative. Absolute paths include the full URL address of an asset, while relative paths show the path of the file relative to the current location of the web page.


HTML is a markup language that defines the basic structure of web pages. Usings tags and attributes, HTML tells browsers how to both process text and present it to the viewer. With HTML, you can specify which part of the document is a title, which is a list, which is an image, and so on. You can also hyperlink a word, embed an image, italicize font, and do much more.

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An HTML file is a standard text format file that contains Hypertext Markup Language (HTML) elements for a specific webpage. These elements describe the type, size, position, and functionality of web page elements such as text, images, tables, and hyperlinks, and they’re often used in combination with other technologies such as Cascading Style Sheets (CSS) and JavaScript to produce interactive and engaging web pages.


HTML tags are pieces of markup language that specify the beginning and end of an HTML element within an HTML document. HTML tags are often considered the root of HTML documents since they contain all HTML-related elements on a page, such as <head>, <body>, <h1>, and <p> tags. In most cases, the <html> tag denotes the start of the document and </html> indicates the end.


HTML5 is the newest version of HTML. The term refers to two things. One is the updated HTML language itself, which has new elements and attributes. The second is the larger set of technologies that work with this new version of HTML — like a new video format — and enable you to build more complex and powerful websites and apps.

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Line Break

A line break is the point at which two lines of text are divided. In HTML, the <br> element creates a line break. You can add it wherever you want text to end on the current line and resume on the next.

The HTML line break element can be used to display poems, song lyrics, or other forms of content in which the division of lines is significant.

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Metadata in HTML is information that describes elements on the webpage but that isn’t displayed to users. Metadata is contained in the <head> element of an HTML document and may include information such as the author of the page, the page title, links to CSS elements, and document keywords. This metadata is used by web browsers to help render HTML documents correctly.

Paragraph Tag

A paragraph tag is an HTML element used to denote the state of a paragraph on a webpage. It is represented in HTML as <p>, while the similar closing tag </p>. In HMTL, paragraphs can take the form of standard text blocks that are separated from other elements by a blank line, or may be used to represent other content groups such as form fields or images.


A tooltip in HTML displays additional information when users hover over a specific element on the page. For example, a tooltip could be added over an image or video to provide more context about the data displayed. Tooltips are shown on top of existing elements and can be positioned to the top, bottom, left, or right of any text depending on how they are described in the HTML syntax.

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Unordered List Tag

The unordered list <ul> tag in HTML is used to produce an unordered list of items that typically appears in bulleted form. It is used with the list <li> tag when the meaning of the list created isn’t dependent on the order of the items listed. For example, the <ul> tag won’t work for a step-by-step list, but is a good choice for a simple list of items.


XHMTL stands for eXtensible Hypertext Markup Language and is designed to extend the functionality of HTML by improving its ability to work with other formats such as XML. The biggest difference between HTML and XHTML is error-handling: While browsers will try to load HTML pages even if they contain errors, XHTML documents must be marked up correctly — also known as being “well-formed” — before being displayed.

Java Terms

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Abstraction in Java is the process of reducing an object to its essential properties and hiding all those that are non-essential. Using abstraction, objects are defined by their properties, attributes, and interfaces, in turn allowing them to occupy reduced storage space without losing their essential characteristics. Abstraction is related to the perceived behavior of the object, meaning that different use cases may require different essential properties.

Base64 Encoding

Base64 encoding is a type of encoding that converts binary data into text using the set of characters in A-Z, a-z, and 0-9+/- — any other characters outside this set will be rejected. Base64 encoding makes it possible to send textual data over networks without corruption or data loss. Java 8 includes a built-in encoder and decoder for Base64 that allows users to leverage three types of encoding: Simple, URL and MIME.


Boolean in Java is one of eight types of “primitive data” within the programming language. Boolean data can be only one of two states: True or false. It is often used in either/or cases where functions or results must be true or false, and can also be used as part of conditional checks using either loops or if statements.


A class in Java acts as a blueprint to create objects. Often thought of as a prototype, a class contains the set of properties or methods that are shared by all objects of a specific type. Classes include a class name, a class keyword, any modifiers for access and any links to larger “superclasses” that help define the class at scale

Compound Addition Assignment Operator

The compound addition assignment operator in Java — denoted as += — allows you to specify the increment increase of a variable. For example, if you define a starting integer of 1 (int a = 1) and then specify a+=2, the system will return a value of 3. If you use the operator ++, meanwhile, the value will only be incremented by one, returning a result of 2.


A Java constructor is a special method type called to create an object within a specific class. Constructors are used to set initial values for the attributes of objects within a class. Java creates constructors for all classes by default, meaning you don’t need to create and call a constructor in order to create an object. The caveat? If you don’t create a constructor, you won’t be able to specify initial object values.

Control Flow

Control flow in Java — also called the flow of control — defines the order in which functions and instructions are executed when a program is running. Control flow statements inside your code define these orders, and are typically executed sequentially from top to bottom, but you can choose to skip specific functions based on a condition, jump to another function or perform a function repeatedly.


Encapsulation in Java is the process of wrapping both variables and methods into a single unit. Using encapsulation allows the variables of classes to be hidden from other classes, and ensures they can only be accessed via the methods of their current class. To encapsulate data in Java, you must both declare the variables of a class as private and provide public setter and getter methods.

Equal to Operator

The equal to operator in Java, denoted as ==, is used to compare two objects based on memory reference. If the objects are identical, the operator will return as true, otherwise it will return as false. This is similar to the equals method, (), with the notable difference that while == is an operator, () is a method. The equal to operator can be used to compare both primitive data and objects, while () can only be used to compare objects.

Final Keyword

The final keyword in Java is used to ensure that the value of an entity cannot be modified in the future. This entity may be a variable, parameter, method, or class. Once the final keyword is declared and initialized, its value cannot be changed. Worth noting? It is possible to declare the keyword without initializing it — in this case, it’s known as a blank final keyword.

Generic Type

T in Java stands for “generic type” and is part of the larger concept of generics in Java. While any letter can be used for this purpose, T is the preferred option. Generic types allow you to parameterize a method, class or interface and determine if the output will be an integer, string or float return type. It’s worth noting that only objects can be used for generic types, since this feature is used during code compiling.

Global Variable

A global variable is a variable that is accessible to all parts of a program. It is typically declared as part of the first lines of code in a program, and streamlines the process of building new applications or functions. While languages such as C and C++ support global variables, Java technically does not, since all variables must be part of a class. Using static variables, however, it is possible to emulate the function of a global variable in Java.


Gulp is a task runner — also called a toolkit — that is used for automating tasks including cache busting, unit testing, magnification and concatenation. Gulp uses the Node.js platform and JavaScript code to help developers run both front-end tasks and manage web applications at scale. Unlike other task runners, Gulp does not create temporary files on disks, but instead passes data directly from one program to another.


A HashMap in Java is a collection class used for storing value and key pairs. It can be implemented as HashMap<Key, Value> or HashMap<K,V>, but does not specify the order of the map generated. While it is similar to the Hashtable class, it does not synchronize value and also permits both null value and null keys. To use the HashMap function, you must import java.util.HashMap.

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Increment Operator

The increment operator in Java — denoted as ++ — increases the value of an integer by 1. This operator can be used in two ways: Post-increment (i++) and pre-increment (++i), which return slightly different results. Post-increment operations return the current value and then the incremented value. This means that if the current value is 1 and you apply a post-increment operation, the result is 1, 2. Pre-increment operations increment the value first and then return the results, which in this case would be 2, 2.


Inheritance in Java is the ability to create a new class from an existing class while keeping the same methods and fields. The new class created is known as a “subclass”, while the original parent class is a “superclass”. The keyword extends is used to perform the inheritance function. For example, a subclass of “truck” could inherit the methods and fields of the superclass “vehicle” to save time and effort.

Instance Variable

An instance variable in Java is one defined without the Static keyword and that exists outside any method declaration. These variables are object-specific, which means that their values are specific to their instance and are not shared among other instances. Instance variables can use any of the four Java access levels: Public, private, protected, or default. They can also be marked as final or transient, but cannot be marked as abstract or synchronized.


An interface in Java is an abstract type used to specify the behavior of a class. It only defines the “what” of this behavior, not the “how”, effectively making it the blueprint of the class. It contains both static constants and abstract methods and is one way to achieve abstraction in Java. Worth noting? While an interface can have both methods and variables, it cannot have a method body.


Java is a programming language developed by Sun Microsystems in 1995. It is a class-based, object-oriented language commonly used for application development and remains one of the most popular languages worldwide. Java is often used in conjunction with the Java Platform to help developers create applications for websites, data centers, and mobile devices. Designed to have limited implementation dependencies, Java is quick and easy to deploy.

Java String

A Java String is a sequence of characters. For example, the word “string” is made up of six characters: s, t, r, i, n, and g. Strings are considered objects in Java programming, and the string class can be used to examine individual characters, compare strings, search strings, and copy string characters. Worth noting? Once a string is created it is immutable and cannot be changed.


The Java Development Kit is a development environment that is used to help developers build components, applications and applets within the Java programming language. It includes tools for both developing and testing applications and is available from Java.com. It is not part of the JRE, and must be downloaded separately. The kit also includes a compiler and debugger.


A literal in Java is any constant value that can be assigned to a variable. Literals in Java are representations of Boolean, numeric, string or character data that allows you to express specific values within a program. In Java, literals are of the int type by default. Modifiers such as “l” or “L” can be used to define literals explicitly as long type.


A method in Java is a block of code that contains a set of instructions that perform a task, also known as a function. Methods only activate when called, and are often used as a template for specific functions that allow code to be reused without the need for it to be rewritten again and again. Methods are easy to modify as required by simply removing or adding a piece of code.

Multiplication Compound Assignment Operator

The multiplication compound assignment operator in Java, denoted as *=, allows you to multiply the variable by the value of the right operand. The output is then assigned to the variable. Consider the example of a = 5. If you use a compound assignment operator of a *=-3, the value returned will be 15. This operator can also be used to repeatedly calculate increasing variable values.


A Java object is an instance of a Java class. To create an object, developers use the keyword “new”, which allows them to define the identity, behavior, and state of the object. While the state of an object is stored in variables (also called fields), methods (also called functions) define an object’s behavior. Objects are created at runtime from classes.


Method overloading in Java is the process of giving two (or more) methods the same name if they differ in parameters and accept different arguments. Depending on the argument passed, the relevant method is called and the others are not. Overloading reduces the number of methods you need to create, and makes it possible to streamline the look and flow of your Java code.


A package in Java is used to create a group of related classes. Packages operate in much the same way as folders in a larger file directory; both help to avoid conflicts and streamline usability. There are two basic types of packages: Built-in packages which are defined by the Java API, and user-defined packages that allow developers to create custom class relationships.

Parameter in Java

Parameters in Java refer to variables that are listed in a method declaration. Parameters must each have a defined data type and unique name — data types include anything from primitives such as integers to reference objects like arrays. Common parameters include the name of the variable, its position, its size and integers representing any change to the variable on the webpage.


A polyfill is a piece of JavaScript code used to implement modern web functionality in older browsers that do not natively support these functions. Polyfills make it possible to offer a more streamlined web experience for visitors using older or outdated browser versions or types. While polyfill can help in cases where browsers implement similar functions in different ways, they’re outpaced at scale by the performance of APIs.


Polymorphism in Java refers to the ability to use similar methods to perform different functions via the property of class inheritance. Classes that are related to one another can inherit the attributes and methods of another class; polymorphism allows these methods to be applied to differing tasks. This makes it possible to reuse existing attributes and methods when creating a new class.

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Remainder Operator

A Remainder Operator in Java — also called a Modulo — is denoted by the symbol % and represents the remainder of two numbers after the operation of division. For example, the operation 15%6 will return an output of 3, which is the remainder of 15 divided by 6. Worth noting? If your numerator is less than your denominator, the Remainder Operator function will return the output as a numerator.

Return in Java

Return in Java is a statement used to return a value when the execution of a method or block is completed. If a return statement is inserted into a loop, the loop will break and the compiler will ignore further statements. All methods are declared with a return type in Java — such as float, int, or double — and returned data should be of the same type as initially declared.

Runtime Environment

The Java Runtime Environment (JRE) is what you receive when you download Java software. The latest version — version 8 — includes the Java Virtual Machine (JVM), Java platform core classes and all supporting Java libraries. The JRE is required to run all Java WebStart applications from a web browser. Development tools such as the Java Development Kit (JDK) are downloaded separately.


Serialization in Java is the process of converting the state of an object into a stream of bytes which can then be saved to a database or transferred over a network. Deserialization is the opposite: Converting byte streams into object states. The serialization process is instance-independent, which means that object serialization and deserialization processes don’t require the same platform to function.


Static is a keyword in Java used to create a constant condition that is the same for all instances of a class. The static keyword can be used with variables, methods, nested classes and blocks. To create a static member, its declaration must be preceded by the keyword static — it will then be accessed before the objects of its class are created and without object reference.

Super Keyword

A super keyword in Java is a type of reference variable which refers to an immediate parent class object. Super keywords are created by default whenever you create a subclass. These keywords can be used to refer an immediate parent class instance variable if the parent and child class have the same fields, invoke the parent class method, or using super() can invoke the parent class constructor.

Python Terms

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Addition Assignment Operator

The Python Addition Assignment Operator, denoted as =+, adds two values together and then assigns the final value to the variable output. In practice, the syntax for this operator is variable_name += value. Consider the value of x = 10. If we use the operator to give a =+ 4, the output value is 14. This operator is often applied to counters or other tools that record the number of times something occurs within a system.


Anaconda is a distribution of the Phyton programming language that is specifically designed to help facilitate scientific computing applications such as machine learning and predictive analytics. This distribution looks to simplify both deployment and package management and can be used with Windows, Linux and macOS. The distribution includes more than 250 packages and can be expanded with 7,500 additional open-source packages.


The Python append function, denoted as append(), adds a single item to an existing list. This function won’t return the entire list with the new item added, but instead modifies the list to add the new item and increases the total size of the list by 1. Items appended to a list can include strings, numbers, dictionaries or another list.


An argument in Python is a value sent to a function when it is called. It is often used interchangeably with the term “parameter”, but since both refer to information passed to a function, but parameters are variables listed inside the parenthesis, while arguments are sent to the function itself. Functions must be called with the correct number of arguments, meaning that if a function expects two arguments, it must be called with 2 arguments, no less and no more.


An array in Python is used to store multiple values in a single variable. While Python does not offer built-in support for arrays, it’s possible to use Python Lists to perform a similar function. An array makes it possible to find specific items from a list of variables by holding multiple values under a single name and refers to each value using a specific index number.


The Python assert keyword is used when debugging code. Using the asset keyword allows you to test if conditions in your code return true or false. If the condition is true, no output occurs. If the condition is false, an AssertionError is raised — you can choose to write a custom message which will be displayed if your code returns false.

Comparison Operator

The Comparison Operator in Python, denoted as ==, is also called the Equality Operator and is used to compare the value of two objects. If the two values are equal, the condition returns as true. If they are not equal, the condition returns as false. This operator is similar to the “is” operator — the difference is that while == compares the value of two objects, “is” determines if two variables point to the same object in memory.


Django is a high-level Python framework built by teams of experienced developers. The framework is designed to produce clean code as quickly as possible, and handles most backend development processes to let developers focus on their applications rather than their integration. Django helps developers avoid common security mistakes and is rapidly scalable to help meet the needs of growing websites.

Else If

The else-if statement in Python is used to check multiple expressions. When the condition for if is false, the statement checks the next condition. If all conditions are determined to be false, the body of “else” is executed as described. This statement is often written as “elif”. While an “if” block in Python can have only one “else” block, multiple “elif” blocks are permitted.

Enumerate Function

The enumerate function in Python converts a data collection object into an enumerate object. Enumerate returns an object that contains a counter as a key for each value within an object, making items within the collection easier to access.

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Exponentiation Operator

The Exponentiation Operator in Python, denoted as **, is used to calculate exponent values of a variable and return the output. For example, in the case of a=5 and b=2, applying the operator a**b returns a value of 25. In effect, the ** indicates the exponentiation of “a” and defines the value of “b” as the exponent. In this case, b=2 squares the value of a — using b=3 would cube the value of a.


Flask is a Python framework that makes it easier to develop web applications. Frameworks are code libraries that contain reusable code extensions for common functions and Flask has emerged as one of the most popular. Flask is what’s known as a “microframework” because it does not require specific tools or libraries and has no database abstraction layer, but can be expanded with the addition of extensions for upload handling, form validation and object-relational mapping.


The Float function in Python is written as float() and is used to return a floating-point number from a provided string or number. This function returns a value based on the argument or parameter passed to it — a blank parameter will return a floating-point output as 0.0, while outputs over the approximate maximum of 1.8 x 10308 will return an infinity (inf) error string.


Python IDLE (Integrated Development and Learning Environment) is an integrated development environment (IDE) included in the default Python package, except for Linux distributions. IDLE is designed to help users get familiar with Python and includes the ability to execute a single statement or create and modify Python scripts. It also includes a full-featured text editor for Python scripts.


The Python index function, denoted as (), lets you find the index position of an item or element in a list of items or a string of characters. Using the () function returns the lowest index position of the specific element, or ValueError if the element does not exist. You can also specify the start and endpoints of the index search using Start_pos and End_pos.


The Python interpreter is part of the language itself — Python is an interpreter language. In practice, this means that after code is written in text form and saved in a .py file, the Python interpreter goes through the code line by line and converts it into a format that computer hardware and software can understand. You can also use the Python shell to execute and display the results of a single command.

Lambda Function

Lambda functions are almost identical to normal Python functions, but with two key differences: Lambda functions have no name and are contained in one line of code. These functions are used to evaluate the expression for a given argument — the function must contain both a value and an operation. For example, where a normal Python might define the name of a function as “y” and use two lines of code, a Lambda function could look like this: lambda y: y+y.


A Python library is a piece of code that can be reused to reproduce specific functions. Adding a library to your program or project means you don’t have to do the work of creating this code yourself. Standard Python deployments come with more than 200 core modules to help improve code functionality, but you can also expand your library with thousands of other components from the Python Package Index (PyPI).


Literals in Python represent the raw data assigned to variables or constants in programming. There are five common types of literals in Python: String, numeric, boolean, collections, and None. These literals are used to denote quantities or notations that do not experience a change in value when programs are executed. Literals streamline the process of assigning constants to Python programming functions rather than redefining these values with each new application.

New Line Character

The New Line Character in Python, denoted as /n, is used in syntax to create a new line. Any characters inserted into a string after /n will be added to the new line. For example, the string “Python is great /n at least that’s what everyone says”, would break the string into two lines: “Python is great”, and on the next line “at least that’s what everyone says.” The /n itself isn’t displayed since the “/” indicates the n is a command, not part of the string itself.

Not Equal to Operator

The Not Equal Operator in Python denoted as !=, is used to determine if operands on either side of the operator are not equal. If the values are not equal, the operator returns as true. If they are equal, it returns as false. In syntax, this is written as Value A != Value B. For example, using A=1 and B=2, the statement A != B returns as true. Worth noting? The operator will return as true if the values of each operand are the same but they are different data types.


NumPy stands for Numerical Python and was created in 2005 by Travis Oliphant. It is a Python library designed to work with arrays and is open source and free to use. While Python lists are often used to serve the purpose of arrays, they can be cumbersome and slow. NumPy array objects are up to 50x faster than traditional Python lists.

Object-Oriented Programming

An object in Python is an instance of a larger class. Where the class works like a blueprint that contains the general parameters, a class assigns actual value to these parameters. For example, while the class “car” includes all of the component parts — such as engines, tires, windows and lights — required to build a car, an object assigns actual values to these parts to produce a specific instance.

Parameter in Python

A parameter in Python is a variable that acts as a placeholder for the values required by a function. When functions are called, these parameters become arguments. While in practice both parameters and arguments are the same things — information passed into a function — parameters are listed inside the parentheses of a function definition, while arguments are the values sent to a function when called.


Parsing in Python is the process of converting code into machine language to check the syntax of the code and ensure it is correct. Python includes a library that acts as a parser, which allows data that is not present in the right format to be converted before processing. Additional parser modules can be added to Python to help provide additional clarity.

Pass Statement

A pass statement in Python is also known as a null statement. When the Python interpreter encounters a pass, it is not ignored but results in no operation (NOP). This is in contrast to a comment, which is entirely ignored by the interpreter. Passes are often used as placeholders for loops or functions that are not yet completed — because they are read but not executed by the interpreter, it’s easy to replace passes with actual code when the time comes.


Python PIP is a package installer for Python that allows you to quickly add Python packages that contain all the files needed for a Python code library. PIP can be used to download packages from the Python Package Index (PyPI) or from other package sources. If you have version 3.4 or later of Python installed, PIP is included by default.


Python is a powerful programming language created by Guido van Rossum in 1991. Python was designed to be an interpreted programming language for general use. An interpreted language means that the programming code gets converted into bytecode and then executed by the interpreter, which in this case, is the Python virtual machine.

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Python 3

Python 3 refers to versions 3.x of the Python framework. First released in 2008, Python 3.0 replaced version 2.0. While some features of version 3.0 were backfilled into 2.0 to help make project migration easier, there are significant differences between these two versions — for example, Python 3 syntax was designed with ease of understanding in mind, whereas Python 2.0 was comparatively complex. The most recent version is Python 3.9.

Python Self

Self in Python provides a way to access the attributes and methods of a class. Different languages use different syntax terms to access the attributes and methods; in C++, “this” is used for access, while self is the counterpart in Python. Self is the first parameter of the methods of a class, but it’s worth noting that the use of “self” isn’t required — you can use any word as the first parameter, but self is the generally accepted convention.


A Python script is a collection of commands in a file that can be executed like a program from the command line of an OS or using a Python interactive shell. These scripts are designed to perform specific functions — in many cases, scripts will contain a set of function definitions followed by a main program that calls these functions.


A set is a data collection type used in Python for storing multiple items in a single variable. Sets in Python are unordered and, as such, are not always consistent in the order they get returned. Furthermore, items in the set are immutable — ie. cannot be changed. However, items can be added and removed.

Duplicates are not permitted with Python data sets and will be removed. It is also noteworthy that the Python set supports any data type — including numbers, strings, and booleans — but also has some support for nested data structures.

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Strings in Python are arrays of bytes that represent Unicode characters. Unlike other languages, however, Python does not have a character data type, which means that a single character is treated as a string with a length of 1. Strings in Python can be surrounded with either single or double quotation marks — this means that “string” is the same as ‘string’ from a syntax perspective.


A tuple in Python stores multiple items within a single variable. Tuples are written using round brackets and are one of the four built-in data types used by Python for data collection storage — List, Set and Dictionary are the other three. Tuples are ordered and unchangeable, meaning they can’t be modified after they’ve been created. They’re also indexed; the first item has index 0, the next 1, and so on.


Variables in Python act as containers that store data values. There is no command for declaring a variable — the moment you assign a data value, a variable is created to store this value. There is also no need to declare a specific type when creating variables, and these types can be changed after they have been set. If you want to know the type of data used by a variable, you can use the type() function.