== About SELinux ==
SELinux stands for ''Security Enhanced Linux'' and is based on research performed at NSA and other locations. Where the normal Unix/Linux security system, based upon file permissions, is a ''discretionary access control'' system (DAC), SELinux is a ''mandatory access control'' system (MAC). This means that it attempts to enforce a consistent policy across the entire system,
regardless of settings that any user has configured.
SELinux decisions are based on the ''security context'' of system resources such as files and processes. The security context consists of a user, role, type, and sensitivity component; you can see the security context of files and processes by adding the <code>-Z</code> option to the <code>ls</code> and <code>ps</code> commands: