Counter Strike (or just CS) is one of the most popular shooter games in the world. But... You don't need installing anything today because this game version is called Portable and it is absolutely free and online now. We think you will not notice any significant difference between classic and online version of Counter Strike, because the difference is maximally in the graphics. Everything else is the same - There are two teams in the game - Terrorists and Counter-Terrorists which fight each other. Moreover you can play also other game modes, for example with zombies. And as always you get a money from each killed rival that you can use to buy new fighting equipment in a shop full of goods. You can experience all of this and even more in singleplayer mode against bots since multiplayer is no longer workig. Have fun!