1. Linux features

Linux is a multi-user, multi-tasking Unix operating system running on a wide range of platforms, including the Intel x86 processor family. Linux is a free, open-source implementation of the POSIX (Portable Operating System Interface uniX) specification, with System V and Berkeley extensions (which means it looks like Unix, but doesn't come from the same source). It is open to networks and other operating systems.

Linux's main singularity is that it is free software (copies can be distributed if accompanied by the corresponding source code), developed collaboratively and largely on a voluntary basis by thousands of programmers around the world.

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