Games should automatically update when you launch them if there is an update available.
All steam games update themselves automatically.
you cant Steam doesnt allow that
In order to update Counter Strike: Source you will need to update the Steam system. See related links for more information.
If you have Terraria on Steam it updates itself once an update is available.
First go to the TOOLS Menu then select Network Update and follow the instructions.
You can either sign up to Steam and they will update the game automatically or you can download the Patches from the official SI Games website
update games yes they do
No games will update your Xbox 360. When you insert a game and it asks you to update, this is a game update.
If you have Steam installed, giving it your CD key should register it and make it update.
Yes you can, you import and add non-steam games to your Steam library. From within the library you can launch and run any games, although 'Steam achievements' will only be available for Steam enabled games.
They don't. Only games distributed and managed by Steam can make use of the Steam API.
Yes, some. Not all of them can be activated on Steam. See the related links for a list of the games that can be activated on Steam and for the instructions on how to activate a game on Steam.