A Linux repository is a storage location from which your system retrieves and installs OS updates and applications. Each repository is a collection of software hosted on a remote server and intended to be used for installing and updating software packages on Linux systems. When you run commands such as “sudo apt update” or “sudo apt upgrade”, you may be pulling package information and package updates from a number of repositories.
Repositories contain thousands of programs. Standard repositories provide a high degree of security, since the software included is thoroughly tested and built to be compatible with a particular distribution and version. So, you can expect the updates to occur with no unexpected “side effects.”
Repositories may be standard or non-standard. Once a non-standard repository has been added to your system’s list of repositories, the system can install software from it, as well as from the standard ones; otherwise, it cannot.
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