Linux in a Nutshell, 6th Edition

Commands on Linux

Linux commands are not the same as standard Unix ones. Most of the commands are provided by the GNU project run by the Free Software Foundation (FSF). GNU means “GNU’s Not Unix” — the first word of the phrase is expanded with infinite recursion.

Benefiting from years of experience with standard Unix utilities and advances in computer science, programmers on the GNU project have managed to create versions of standard tools that have more features, run faster and more efficiently, and lack the bugs and inconsistencies that persist in the original standard versions.

While GNU provided the programming utilities and standard commands such as grep, many of the system and network administration tools on Linux came from the Berkeley Software Distribution (BSD). In addition, some people wrote tools that specifically allow Linux to deal with special issues such as filesystems. This book documents the standard Unix commands that are commonly available on most Linux distributions.

The third type of software most commonly run on Linux is the X Window System, ported by the XFree86 and X.org projects to standard Intel chips. This book does not discuss the X Window System; see the O’Reilly book Running Linux, by Matthias Kalle Dalheimer and Matt Welsh, for an introduction to X.