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.

sourceforge provides free & fast open source software downloads and development, and business software reviews and comparisons featuring the largest open source and business software directory.

non-judgmental guidance on choosing a license for your open source project

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.

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

home page of the apache software foundation

gtk is a free and open-source cross-platform widget toolkit for creating graphical user interfaces.

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.