This page last updated 20060709


The Gnu toolkit includes the various shell programs and the "classic" unix commands, such as ls, vi, and so on. They are distributed in the /bin, /sbin, /usr/bin, and /usr/sbin directories.

  • in /bin # this stores the most-used commands
    in CentOS 4 there are a little less than 100 commands in the /bin directory. See them all

  • in /sbin # this stores system commands, for use by the system administrator, they have to do with managing kernel and daemon processes. In CentOS 4 there are over 200 commands.

  • in /usr/bin # there are over 3000 commands in CentOS 4. They are for users to use.

  • in /usr/sbin # these have to do with managing daemon and application processes mainly, though there are some that have to do with kernel management. There are nearly 600 commands in this directory in CentOS 4.

  • the BASH shell # /bin/bash is the default shell. there are about 50 commands in the BASH shell, but that's not a good indicator of complexity, as there are over two dozen operators and metacharacters that combine with the commands.
    see the help output for the BASH shell
    see the BASH tutorial more to come