Add a PPA to your system
with a single line in your terminal
step1:on the PPA's overview page,look for the heading that reads Adding this PPA to your system.Make a note of the PPA's location, which looks like:
paa:gwibber-daily/ppa
step2:open a terminal and enter:
sudo add-apt-repository paa:user/ppa-name // replace ppa:user/ppa-name with the PPA's location that you noted above.
// your system will now fetch the PPA's key.This enables your ubuntu system to verify that the packages in the PPA habe not been interfered with since they were built.
step3:now as a one-off,you shuld tell your system to pull down the latest list of software from each archive it knows about,including the PPA you just added:
sudo apt-get update // ready to start installing software from the PPA!
with editting /etc/apt/sources.list
sudo vim /etc/apt/sources.list
deb [trust=true] http://ppa.xxx.xxx/xx/xx/xx xxx main
deb-src [trust=true] http://ppa.xxx.xxx/xx/xx/xx xxx main