G-Arena and Xfire?

i wanna know what is G-Arena and Xfire ? how to use it ?

Garena is a gaming client, it is mostly used for play warcraft III dota online.....and almost all the time more than 200 pakistani players are online

to play dota online just get urself warcraft III 1.22 frozen throne, and download garena from garena.com, make an account at garena...and enjoy gaming

400.....

^ and about Xfire ?