Software that installs and updates applications in a Linux or Unix environment. A package manager supports the version of the OS being used and functions as the control program for installations and updates. To install another app, users open their package manager (PM) and search by title. Linux package managers are like online app stores that download, install and update the apps.
In contrast, when an app is downloaded directly from a vendor, as have Windows and Mac apps for decades, the apps self install, and the vendors notify the users when an update is ready. However, there are so many different versions of Linux that Linux distributors are obliged to compile a wide variety of free apps and utilities to make sure they work and store them in their own repository. See Linux
and install program