Free and open-source software (FOSS) is software that is distributed in a manner that allows its users to run the software for any purpose, to redistribute copies of it, and to examine, study, and modify, the source code. FOSS is also a loosely associated movement of multiple organizations, foundations, communities and individuals who share basic philosophical perspectives and collaborate practically, but might diverge in detail questions.
The Cygwin installation directory has a directory layout that is similar to the root file system of Unix-like systems, with familiar directories, such as /bin, /home, /etc, /usr, /var. Cygwin installs with hundreds of command-line tools and other programs commonly found on a Unix-like system. Additionally, many applications may be installed from a packaging system. The terminal emulator Mintty is the default command-line interface provided to interact with the environment.
Cygwin provides native integration of Windows-based applications. Thus it is possible to launch Windows applications from the Cygwin environment, as well as to use Cygwin tools and applications within the Windows operating context. (Full article...)