Python
Python Released
Guido Van Rossum released Python (version 0.9.0) to the alt.sources Usenet group. Already present at this stage in development were classes with inheritance, exception handling, functions, and the core datatypes of list, dict, str and so on. Also in this initial release was a module system. It was heavily inspired by ABC, a programming language that Guido spent some time implementing at CWI (Centrum Wiskunde & Informatica) in Netherlands.

Python 1.0
Python reached version 1.0 in January 1994. The major new features included in this release were the functional programming tools lambda, map, filter and reduce.

Zope
Zope is a family of free and open-source web application servers written in Python, and their associated online community. Zope stands for "Z Object Publishing Environment", and was the first system using the now common object publishing methodology for the Web. Over the last few years, the Zope community has spawned several additional web frameworks with disparate aims and principles, but sharing philosophy, people, and source code. Zope 2 is still the most widespread of these frameworks, largely thanks to the Plone content management system, which runs on Zope 2.

Python is GPL Compatible
Python 1.6.1 is released with a new GPL-compatible license.

Python 2.0
Python 2.0 was released with the new list comprehension feature, a full garbage collector, and support for unicode.
SciPy
SciPy is a free and open-source Python library used for scientific computing and technical computing. SciPy contains modules for optimization, linear algebra, integration, interpolation, special functions, FFT, signal and image processing, ODE solvers and other tasks common in science and engineering. SciPy was born around 2001, when Travis Oliphant, Eric Jones and Pearu Peterson merged their modules in one scientific super package.

Python Software Foundation
The Python Software Foundation (PSF) launched on March 6, 2001. The mission of the foundation is to foster development of the Python community and is responsible for various processes within the Python community, including developing the core Python distribution, managing intellectual rights, developer conferences including PyCon, and raising funds.

Natural Language Toolkit
The Natural Language Toolkit, or more commonly NLTK, is a suite of libraries and programs for symbolic and statistical natural language processing (NLP) for English written in the Python programming language. It was developed by Steven Bird and Edward Loper in the Department of Computer and Information Science at the University of Pennsylvania.

IPython
IPython (Interactive Python) is a command shell for interactive computing in multiple programming languages, originally developed for the Python programming language, that offers introspection, rich media, shell syntax, tab completion, and history. It was created by Fernando Perez while at the University of Colorado.

Matplotlib
Matplotlib is a plotting library for the Python programming language and its numerical mathematics extension NumPy. It provides an object-oriented API for embedding plots into applications using general-purpose GUI toolkits like Tkinter, wxPython, Qt, or GTK+. Matplotlib was originally written by John D. Hunter.

SymPy
SymPy is an open-source Python library for symbolic computation. It provides computer algebra capabilities either as a standalone application, as a library to other applications, or live on the web. SymPy includes features ranging from basic symbolic arithmetic to calculus, algebra, discrete mathematics and quantum physics. It is capable of formatting the result of the computations as LaTeX code. SymPy is free software and is licensed under New BSD License. The lead developers are Ondřej Čertík and Aaron Meurer. It was started in 2005 by Ondřej Čertík.

NumPy
NumPy is a library for the Python programming language, adding support for large, multi-dimensional arrays and matrices, along with a large collection of high-level mathematical functions to operate on these arrays. The ancestor of NumPy, Numeric, was originally created by Jim Hugunin with contributions from several other developers. In 2005, Travis Oliphant created NumPy by incorporating features of the competing Numarray into Numeric, with extensive modifications.

SageMath
SageMath (previously Sage or SAGE, "System for Algebra and Geometry Experimentation") is a computer algebra system (CAS) with features covering many aspects of mathematics, including algebra, combinatorics, graph theory, numerical analysis, number theory, calculus and statistics. The first version of SageMath was released on 24 February 2005 as free and open-source software under the terms of the GNU General Public License version 2, with the initial goals of creating an "open source alternative to Magma, Maple, Mathematica, and MATLAB". The originator and leader of the SageMath project, William Stein, was a mathematician at the University of Washington.

Django
Django is a Python-based free and open-source web framework that follows the model-template-views (MTV) architectural pattern. It is maintained by the Django Software Foundation (DSF). Django was created in the fall of 2003, when the web programmers at the Lawrence Journal-World newspaper, Adrian Holovaty and Simon Willison, began using Python to build applications. It was released as open source in 2005.

Scikit-learn
Scikit-learn is a free software machine learning library for the Python programming language. It features various classification, regression and clustering algorithms including support vector machines, random forests, gradient boosting, k-means and DBSCAN, and is designed to interoperate with the Python numerical and scientific libraries NumPy and SciPy. The scikit-learn project started as scikits.learn, a Google Summer of Code project by David Cournapeau. In 2010 Fabian Pedregosa, Gael Varoquaux, Alexandre Gramfort and Vincent Michel, all from the French Institute for Research in Computer Science and Automation in Rocquencourt, France, took leadership of the project and made the first public release on February the 1st 2010.

Web2py
Web2py was originally designed by Massimo DiPierro as a teaching tool with emphasis on ease of use and deployment. The design of web2py was inspired by the Ruby on Rails and Django frameworks. Like these frameworks, web2py focuses on rapid development, favors convention over configuration approach and follows a model–view–controller (MVC) architectural pattern.

Theano
Theano is a Python library and optimizing compiler for manipulating and evaluating mathematical expressions, especially matrix-valued ones. In Theano, computations are expressed using a NumPy-esque syntax and compiled to run efficiently on either CPU or GPU architectures. Theano is an open source project primarily developed by the Montreal Institute for Learning Algorithms.

Pandas
Pandas is a software library written for the Python programming language for data manipulation and analysis. In particular, it offers data structures and operations for manipulating numerical tables and time series. Developer Wes McKinney started working on pandas in 2008 while at AQR Capital Management out of the need for a high performance, flexible tool to perform quantitative analysis on financial data. Before leaving AQR he was able to convince management to allow him to open source the library.

Python 3.0
Python 3.0 came with several new features and enhancements, along with a number of deprecated features. The emphasis in Python 3 had been on the removal of duplicate programming constructs and modules. Python 3 is not backwards compatible with Python 2.x.
Flask
Flask is a micro web framework written in Python created by Armin Ronacher. It is classified as a microframework because it does not require particular tools or libraries. It has no database abstraction layer, form validation, or any other components where pre-existing third-party libraries provide common functions. However, Flask supports extensions that can add application features as if they were implemented in Flask itself. Extensions exist for object-relational mappers, form validation, upload handling, various open authentication technologies and several common framework related tools.

OpenStack
OpenStack is a free open standard cloud computing platform, mostly deployed as infrastructure-as-a-service (IaaS) in both public and private clouds where virtual servers and other resources are made available to users.

pip
pip is a package-management system written in Python used to install and manage software packages. First introduced as pyinstall in 2008 by Ian Bicking (the creator of the virtualenv package) as an alternative to easy_install, pip was chosen as the new name from one of several suggestions that the creator received on his blog post. According to Bicking himself, the name is a recursive acronym for "Pip Installs Packages". In 2011, the Python Packaging Authority (PyPA) was created to take over the maintenance of pip and virtualenv from Bicking, led by Carl Meyer, Brian Rosner, and Jannis Leidel.

Seaborn
Seaborn is a library for making statistical graphics in Python. It is built on top of matplotlib and closely integrated with pandas data structures. It was developed by Michael Waskom.

Ansible
Ansible is an open-source software provisioning, configuration management, and application-deployment tool enabling infrastructure as code. Ansible was written by Michael DeHaan and acquired by Red Hat in 2015.

Anaconda
Anaconda is a distribution of the Python and R programming languages for scientific computing (data science, machine learning applications, large-scale data processing, predictive analytics, etc.), that aims to simplify package management and deployment. It is developed and maintained by Anaconda, Inc., which was founded by Peter Wang and Travis Oliphant in 2012.

NumFOCUS
NumFOCUS is a noprofit with the mission to promote open practices in research, data, and scientific computing by serving as a fiscal sponsor for open source projects and organizing community-driven educational programs. Travis Oliphant (author of NumPy), Fernando Pérez (author of IPython), Perry Greenfield (author of Numarray and Astropy), John Hunter (author of Matplotlib), Jarrod Millman (release manager for SciPy), and Anthony Scopatz (who came up with the name “NumFOCUS”) became the founding board of NumFOCUS. Leah Silen was selected as the founding Executive Director. In fall of 2012, NumFOCUS received 501(c)(3) public charity status as a nonprofit in the United States.

Jupyter
Project Jupyter is a project and community, whose goal is to "develop open-source software, open-standards, and services for interactive computing across dozens of programming languages". It was spun off from IPython in 2014 by Fernando Pérez, Brian Granger, Min Ragan-Kelley, Thomas Kluyver, Matthias Bussonnier, Paul Ivanov, Damián Avila, Kyle Kelley, among others. Project Jupyter's name is a reference to the three core programming languages supported by Jupyter, which are Julia, Python and R, and also a homage to Galileo's notebooks recording the discovery of the moons of Jupiter. Project Jupyter has developed and supported the interactive computing products Jupyter Notebook, JupyterHub, and JupyterLab.

spaCy
spaCy is an open-source software library for advanced natural language processing, written in the programming languages Python and Cython. The library is published under the MIT license and its main developers are Matthew Honnibal and Ines Montani.

Keras
Keras is an open-source software library that provides a Python interface for artificial neural networks. Keras contains numerous implementations of commonly used neural-network building blocks such as layers, objectives, activation functions, optimizers, and a host of tools to make working with image and text data easier to simplify the coding necessary for writing deep neural network code. It was developed as part of the research effort of project ONEIROS (Open-ended Neuro-Electronic Intelligent Robot Operating System), and its primary author and maintainer is François Chollet.

TensorFlow
TensorFlow is a free and open-source software library for machine learning. It can be used across a range of tasks but has a particular focus on training and inference of deep neural networks. Tensorflow is a symbolic math library based on dataflow and differentiable programming. It is used for both research and production at Google. TensorFlow was developed by the Google Brain team for internal Google use. It was released under the Apache License 2.0 in 2015.

PyTorch
PyTorch is an open source machine learning library based on the Torch library, used for applications such as computer vision and natural language processing, primarily developed by Facebook's AI Research lab (FAIR). It is free and open-source software released under the Modified BSD license.
