Python is rising in popularity and may well become the most popular and used language in the world! It is not only used by small start ups but also by big corporations like google, dropbox and instagram to build their sites. One reason for its popularity lies in the simplcity of its code but it is still a very powerful language indeed. From everything from game design to high end application development, Python will do the job!
GYP (Generate Your Projects), a build automation tool (similar to CMake and Premake) designed to generate native IDE project files (e.g., Visual Studio, Xcode, etc.) from a single configuration
VisTrails, a scientific workflow and provenance management software with visual programming interface and integrated visualization (via Matplotlib, VTK).
Mathics, an open-source implementation of the Mathematica programming language
Matplotlib, an extension providing MATLAB-like plotting and mathematical functions
NumPy, a language extension that adds support for large and fast, multi-dimensional arrays and matrices
Plotly is a scientific plotting library for creating browser-based graphs.
SageMath is a large mathematical software application which integrates the work of nearly 100 free software projects.
SymPy, a symbolic mathematical calculations package
Additional development packages
Cheetah, a Python-powered template engine and code-generation tool
Cherry, a non-WYSIWYG templating language developed for CherryPy framework
Construct, a python library for the declarative construction and deconstruction of data structures
Genshi, a template engine for XML-based vocabularies
IPython, a development shell both written in and designed for Python
Jinja, a Python-powered template engine, inspired by Django's template engine
Kid, simple template engine for XML-based vocabularies
Mako, a non-XML template library which compiles into Python modules for maximum performance
mod_python, an Apache module allowing direct integration of Python scripts with the Apache web server
PyObjC, a Python to Objective-C bridge that allows writing OS X software in Python
Robot Framework, a generic test automation framework for acceptance testing and acceptance test-driven development (ATDD)
Setuptools, a package development process library designed to facilitate packaging Python projects by enhancing the Python distutils (distribution utilities) standard library.
GNAT The GNAT programming chain tool (Ada language implementation in GNU gcc), as a GNATcoll reusable components for the applications (with or without PyGTK) and as a scripting language for the commands in the GPS programming environment
Houdini highly evolved 3D animation package, fully extensible using python
NASA is using Python to implement a CAD/CAE/PDM repository and model management, integration, and transformation system which will be the core infrastructure for its next-generation collaborative engineering environment[citation needed]. It is also the development language for OpenMDAO, a framework developed by NASA for solving multidisciplinary design optimization problems.
"Python has been an important part of Google since the beginning, and remains so as the system grows and evolves. Today dozens of Google engineers use Python."[3]
reddit was originally written in Common Lisp, but was rewritten in Python in 2005[4]
YouTube uses Python "to produce maintainable features in record times, with a minimum of developers"[5]
Enthought uses python as the main language for countless custom applications in Geophysics, Financial applications, Astrophysics, simulations for consumer product companies, ...
EDF uses Python for their finite element solver Code Aster in combination with Fortran
Python implementations
CPython – The reference implementation, written in C89
Cython is a programming language to simplify writing C and C++ extension modules for the CPython Python runtime.
PyPy – Python (originally) coded in Python, used in conjunction RPython, a restricted subset of Python that is amenable to static analysis and therefore a JIT.
Pyston - an open source Python implementation using JIT techniques. Currently targeting Python 2 support.
Parrot – Virtual machine being developed mainly as the runtime for Perl 6, but with the intent to also support dynamic languages like Python, Ruby, Tcl, etc.
Pyjs – a framework (based on GWT concept) for developing client-side Python-based web applications, including a stand-alone Python-to-JavaScript compiler, an Ajax framework and widget toolkit