How to add PPA repository in ubuntu linux

The PPA is a linux repository on a non-official, used to accommodate the developer's applications which are not included into the indi repository official/official. Often when we want to install an application program on linux, it turns out there hasn't been in the official repository. The existence of this PPA repository, we do not need to download the source application, and then mengcompile himself of course troublesome and not necessarily the application runs perfect.

We just need to add an entry into our repository ppa, and applications that exist on the ppa repository can we install with package manager.

There are several ways to add the ppa repository, I am just going to cover 2 ways, namely through the terminal and gui.
Add the PPA repository through the terminal

Open a terminal emulator, and then enter the command:

[code lang="bash"] sudo add-apt-repository ppa: achadwick/mypaint-testing [/code]

Which the ppa: achadwick/mypaint-testing is the ppa entry that you can get on the website launcpad.net for the application in question.
Add the PPA repository through GUI (Software Source)

Open Software Sources, and then enter your password.

then:

Click the tab of the PPA
Click Add new PPA
Copas entry PPA
Click OK, and then follow the process.
If the process is completed, click refresh list