Python is a widely used high-level, general-purpose, interpreted, dynamic programming language. Its design philosophy emphasizes code readability, and its syntax allows programmers to express concepts in fewer lines of code than would be possible in languages such as C++ or Java.
It can be used to serve a number of purposes eg software application development, scripting, artificial intelligence, data science, etc ( full list https://www.python.org/about/success/)
Examples of systems built in python include the following; Google, Instagram, Quora, Yahoo Maps, Hipmunk, BitTorrent, Dropbox, YouTube etcstrong>(full list from https://en.wikipedia.org/wiki/List_of_Python_software)
Python web frameworks
Pyramid which is great for; getting started quickly, developers working on API projects, prototyping a concept, developing large web applications, such as a CMS or a KMS.
Bottle (Simple); is a simple micro framework that provides minimal tools out of the box (routing, templating and a small abstraction over WSGI). It is great for developers looking for flexibility, creating a web API, people who want to build something really simple.
Flask (Nimble), strives to be simple and small; the entire framework consists of a handful of modules. It is great for; learning programming, developers who care about best practices and "tasteful" code, developers who want to prototype something quickly, Developers who need a standalone applications.
Django (Powerful); is by far the largest high-level Python-based web framework that encourages rapid development and clean, pragmatic design. Built by experienced developers, it takes care of much of the hassle of Web development, so you can focus on writing your app without needing to reinvent the wheel. It is supported by a large and active community. It comes with a powerful admin interface as well as many other features out of the box. Django offers model-based forms, has its own templating language, and has excellent documentation available. Django is great for; developers who like to share ideas with each other via online forums, developers who want to build something quickly with powerful built-in tools, ridiculously fast, reassuringly secure, exceedingly scalable. (https://www.djangoproject.com/)
Useful Django apps( South (for schema and data migrations), Django Celery, Django Rest Framework or TastyPie, Django Extensions), Time-tested, Tons of Django packages available, excellent documentation, supportive Django community, Fully Featured Out Of The Box, Portability, Built-In Admin Panel, Scalability, Django is fast, Django supports a number of CMS eg mezzanine, django-cms, etc