github is where over 100 million developers shape the future of software, together. contribute to the open source community, manage your git repositories, review code like a pro, track bugs and features, power your ci/cd and devops workflows, and secure code before you commit it.

gimp - the gnu image manipulation program: the free and open source image editor

stack overflow is the largest, most trusted online community for developers to learn, share​ ​their programming ​knowledge, and build their careers.

ghostscript is the #1 pdl conversion and interpreter tool available, offering native rendering of pdf, postscript, pcl, xps, raster and vector files, as well as ascii text.

q&a for ubuntu users and developers

since 1983, developing the free unix style operating system gnu, so that computer users can have the freedom to share and improve the software they use.

a computer science portal for geeks. it contains well written, well thought and well explained computer science and programming articles, quizzes and practice/competitive programming/company interview questions.

the python package index (pypi) is a repository of software for the python programming language.

well organized and easy to understand web building tutorials with lots of examples of how to use html, css, javascript, sql, python, php, bootstrap, java, xml and more.

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