Key Differences Between Python 2 and Python 3

Python 2 and 3 are two of the most popular programming languages that have led to advancements in various fields, such as Data Science, Software Engineering, and Artificial Intelligence. They're both incredibly versatile and have a ton of applications. Many people are unsure which version to learn or whether they should learn at all.

Today, we will explore the differences between Python 2 and 3 - two major versions of the same programming language. Although they share many standard features, some key differences may make one version more appealing to you than the other. In recent years, there has been a lot of debate about which of these two versions is superior.

With that said, let's get started.

Why use Python 2?

Python 2 was released in 2000 and has been the most popular version of Python for many years. It's still used extensively, especially in large projects with a lot of legacy code.

One of the main reasons why Python 2 is still so popular is because it's backward compatible. This means that you can run Python 2 code on a Python 3 interpreter and vice versa. However, some differences between the two versions can cause problems when running code meant for one version on the other.

Another reason why people continue to use Python 2 is because of its wide range of libraries. While many popular libraries have been ported to Python 3, some still haven't made the switch yet. This can be frustrating for developers who want to use the latest and most excellent tools but need to maintain compatibility with older libraries.

Why use Python 3?

Python 3 was released in 2008, and it has slowly been gaining popularity ever since. Many new projects are now starting to use Python 3, and more and more libraries are being ported over as well.

One of the main reasons to use Python 3 is because it's the future of the language. Python 2 will eventually be phased out, and all new development will happen on Python 3. If you're just learning Python, it makes sense to start with the latest version so that you don't have to worry about migrating your code later.

Another advantage of Python 3 is that it's not backward compatible with Python 2. This might sound like a downside, but it offers some benefits. Since Python 3 is not compatible with Python 2, it's easier to write code specifically designed for Python 3. This can lead to cleaner and more maintainable code in the long run.

Python 2 vs. Python 3

Now that we've gone over some of the significant reasons to use Python 2 or 3 let's take a more detailed look at the key differences between these two versions.

Storage of Strings

One of the most significant differences is that Python 3 uses Unicode for all strings, whereas Python 2 uses ASCII encoding. This difference can cause some issues when running code meant for one version on the other.

Annotations

Another difference is that Python 3 supports type annotations. Type annotations are a way of specifying the type of a variable when declaring it. This can help with code clarity and maintainability. Python 2 does not support type annotations.

Exception Handling

Python 3 also has some improvements to exception handling. In Python 2, exceptions are caught by checking for the specific exception type. In Python 3, exceptions are caught by matching the value of the exception. This change makes it easier to handle unexpected exceptions in your code.

Print Statement

Python 3 removed some features that were considered to be deprecated in Python 2. One example is the 'print' statement. In Python 2, you can use the print statement without parentheses, but in Python 3, you must use parentheses.

Syntax

Python 3 also introduced some changes to the syntax of the language. One example is the 'print' statement (as we just saw). Other examples include the 'range' and the 'next' functions.

Print Example:

In Python 2, this statement would print the string "Hello, World!" to the screen. In Python 3, this statement would cause an error.

Range Example:

In Python 2, this code would create a list of integers from 0 to 9. In Python 3, this code would produce an iterator from 0 to 9.

Iterator Example:

In Python 2, this code would return the next item in the 'iterator' object. In Python 3, this code would cause an error.

Career Opportunities

Although Python 2 is still widely used, Python 3 is slowly becoming the standard. This means that there are more opportunities for developers who know Python 3. If you're just starting, learning Python 3 will give you a better chance of landing a job in the future.

For more information on the differences, check out this video:

These are just some of the most significant differences between Python 2 and 3. As you can see, these two versions have quite a few changes. If you're planning on running Python code on both versions, it's important to be aware of these differences.  

So, which version should you learn?

Choosing between Python 2 and 3 can be challenging, especially if you're just starting out. However, there are some things to keep in mind that might help you make a decision.

If you're starting a new project from scratch, you should use Python 3. It's the future of the language, and it offers some benefits over Python 2 that can make your life easier in the long run.

However, if you need to maintain compatibility with Python 2 code or libraries, you'll need to use Python 2 for your project. In this case, it's probably best to learn both versions to be as versatile as possible.