Counter-Strike vs Counter-Strike: Source
Counter-Strike
Counter-Strike is one of the the pioneers of the team-based multiplayer, action-shooter game genre and it is thanks to these games that we now have games like Combat Arms or even Blacklight. That said, you probably have heard of Counter-Strike so I'll keep this simple. The game places you into a team - either as Terrorists or Counter-Terrorists - before the match and your team will be given an objective to do, be it taking out enemy sites, rescue hostages or simply taking out the other team. For the "vanilla" version of Counter-Strike, the multiplayer community is pretty nice overall and definitely not as toxic as in the latest installment.However, the graphics can be rather painfully outdated in this game. So, unless you are feeling nostalgic or if you don't really mind old graphics, then Counter-Strike might just be the game for you.
Counter-Strike: Source
Counter-Strike: Source is the second installment in the incredibly popular MMOFPS franchise, Counter-Strike. Despite being a rather old game, Counter-Strike: Source still manages to hold its own in this day and age, with some even claming this game is so much better than the more recent Counter-Strike: Global Offensive or CS:GO. Unlike CS:GO, this game doesn't offer buyable skins and the most important thing - the community is definitely not as toxic as those you'd find in the CS:GO servers. Although the game modes can be rather limited, you can easily find some really good new ones in modded servers.So, if you're looking for the Counter-Strike experience without all the hate that most new players will get, this might be a good game to start.