ArmA 2 is set in the near future, year 2009, in a fictional post soviet country called Chernarus. Players will be sent as members of a United States Marine Corps Force Recon squad to this country to prevent further civilian casualties and ensure ongoing stability there. Arma 2 is based on the latest generation technology, offering large ?scale game world, authentic and extremely detailed modern units, weapons, vehicles and enviroments, challenging single player and vast array of multiplayer options.Go to: http://store.steampowered.com/ and download STEAM client
Click “Install Steam” (from the upper right corner)
Install and start application, login with your Account name and Password (create one if you don’t have).
Please follow these instructions to activate a new retail purchase on Steam:
Launch Steam and log into your Steam account.
Click the Games Menu.
Choose Activate a Product on Steam…
Follow the onscreen instructions to complete the process.
After successful code verification go to the “MY GAMES” tab and start downloading.