Steamcloud is the name of a feature developed for the Steam content distribution platform that allows players to store their relevant user data online via Steam. This means that things like saved games, keyboard configuration, user profile and other preferences and settings unique to each Steam user will be stored on Valve's servers, rather than on your home computer, so you don't lose them when you reinstall - and you have no limit on how much information of this type can be stored for you. Whether you log onto Steam from your PC, your friend's PC, at a LAN center or anywhere else, you will always have your preferences and saved games.

Steam Cloud is now offered to third-party developers as part of the free Steamworks suite, so you can expect to see it in many future titles released through Steam. All Valve titles will eventually be updated to use Steam Cloud but so far Left 4 Dead is the only game to enable it.