What are Repositories?

What are Repositories?-There are literally thousands of Ubuntu programs available to meet the needs of Ubuntu users. Many of these programs are stored in software archives commonly referred to as repositories. Repositories make it very easy to install new software onto Ubuntu using an Internet connection, while also providing a high level of security, as each program available in the repositories is thoroughly tested and built specifically for each version of Ubuntu.

The Ubuntu software repositories are organized into four separate areas or "components", according to the level of support offered by Ubuntu and whether or not the program in question complies with Ubuntu's Free Software Philosophy.

The repository components are:

    Main - Officially supported software.

    Restricted - Supported software that is not available under a completely free license.

    Universe - Community maintained software, i.e. not officially supported software.

    Multiverse - Software that is not free.

For more information regarding the Ubuntu Repository components

The Ubuntu Install CDs contain software from the "Main" and "Restricted" components of the repositories. Once your system is made aware of the Internet-based locations for these repositories, many more software programs are available for installation. By using the software package management tools already installed on your system, you can search for, install and update any piece of software directly over the Internet, without the need for the CD.

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