The /etc/apt/sources.list file contains a list of sources from which apt can download indexes of binary and source packages .

In this tutorial , we will explain the format of a source in sources.list . We will also explain what is an index file , what is a distribution , what is a distribution release file , what are a distribution components , and we will give an example of a sources.list file .

The man-db package is used to search for documentation under Linux . It is used by Debian , fedora , and other Linux distributions .

The man-db package contains the binaries which are used for searching and for reading the documentation :

whatis , apropos , man

It also contains utilities used to maintain the documentation:

mandb , manpath , smanpath.config

This article will explain , what is the manual , the manual section , the manual page . It will also explain what is the man-db package and what is whatis , apropos and the man commands .