Python is a very popular high-level programming language, created by Guido Van Rossum and first released in 1991. Python is an interpreted language. Its coding-syntax is very straight forward, kind of sentences in English.

What makes it more popular is the support from the wide python developers community. If you are working in python development, and having some issue at any point of time, then just search on stack-over flow , you will get your solution , 99.9%, else, you can always hit and try.

Python contains very nice web dev frameworks (Micro and Macro) like Most popular is DJANGO, then my favorite i.e.  FLASK then BOTTLE, CHERRYPY, PYRAMID, WEB2PY, TORNADO, etc.

All of them are unique and defines purpose of usage , like if you want to develop a big application which contains lot of content then Django is best for that,  but if your website is small and contains light traffic the Flask , Bottle, Cherrypy, etc  will be best.

There are also different game development engines provided by python, like  pygame,etc.

Python flask example

Data Science - Machine Learning :

“ Data science, also known as data-driven science, is an interdisciplinary field about scientific methods, processes, and systems to extract knowledge or insights from data in various forms, either structured or unstructured, similar to data mining ”. (source - wikipedia)

“Machine learning is a field of computer science that gives computers the ability to learn without being explicitly programmed. Arthur Samuel, an American pioneer in the field of computer gaming and artificial intelligence, coined the term "Machine Learning" in 1959 while at IBM.” (source - wikipedia)

Python is very popular in data science and analytics, Its libraries, like Pandas, Numpy, Scipy, Scikit-learn(most popular), Matplotlib for plotting, Beautifulsoup for web-scrapping,etc are very widely used all over the development environments across the globe.

The simplicity of usage and performance of python makes it first choice for development in any domain of development, whether it is gui based development, Web based development, or Data Science Machine Learning.