How do you install an application on Linux? As with many operating systems, there isn’t just one answer to that question. Applications can come from so many sources—it’s nearly impossible to count—and each development team may deliver their software whatever way they feel is best. Knowing how to install what you’re given is part of being a true power user of your OS.
Repositories
For well over a decade, Linux has used software repositories to distribute software. A “repository” in this context is a public server hosting installable software packages. A Linux distribution provides a command, and usually a graphical interface to that command, that pulls the software from the server and installs it onto your computer.
Read more at OpenSource.com