Acronym for Counter-Strike:Source.
CS?! Let's play CS:S, it's got sweet graphics!
counter-strike: source, far inferior to the original 1.6 version, but fun for rich kids who have loads of money, and also a leading reason why CAL is undergoing much internal turmoil given the recent league changes
CS:S - man, that really ruined CAL...we're all going to UGS