Complex sentence: GNU provides POSIX compliance along with extensions of its own, hence the name "GNU/Linux" describes the whole operating system as stated by the Free Software Foundation and complies with the broad concept of operating system.
Split into simpler sentences: GNU provides POSIX compliance along with extensions of its own. Hence, the name "GNU/Linux" describes the whole operating system as stated by the Free Software Foundation and complies with the broad concept of operating system.