The preferred method of installing programs is via the package managers described in this chapter. However, although the Ubuntu package archives are very large, it is possible that you may wish to install a package which is not available in the Ubuntu archives. If this happens, you can also download and install files from websites.
Caution: It is important to ensure that any files you download come from a safe source before installing them.
There are many different kinds of Linux package files. Most of these are associated with the package managers of specific Linux distributions. Examples are Debian Package files (.deb files), Redhat Package Manager files (.rpm files), and Tarballs (.tar files).
This section deals with installing these single files.
Warning: It is not guaranteed that these files will be compatible with your system and you will not receive security updates if you install these files. For these reasons, if you wish to install a program, always use a native Ubuntu package of the application available through a package manager, if there is one available.