What exactly is Steam?

There is no cost for a Steam Account. You can just play the games you buy for free. However, you need an online connection to play any game from your steam library, even ones that don't have any online modes. You will find A LOT more is available on Steam than XBLA or PSN.

Steam is similar to Xbox Live in that way, yes. You buy games on steam and install the directly to your hard drive. No need for a disc. All of your purchases are also backed up on the Steam servers, so you can redownload them on as many systems as you like (you will have to log in with your account before you can play them).

However, the big catch with Steam is that it is also a game launcher. Every game you buy on Steam MUST be launched from within Steam. So, on the off-chance that the Steam company goes bankrupt or something (unlikely), your purchases are lost, and any game you have already installed is rendered unplayable. Again, highly unlikely, but it's always a possibility. It's the risk we run for the convenience of PC gaming. ;)

Steam accounts are also free, yes. You only pay for the games.

@Rizer

Ah, I hadn't heard that. Oh well, we hopefully will never end up in that situation anyway. ;)

That's the gist of it. Steam is entirely free to use, you only pay for the games you wish to buy of course. Which will be saved to your account for you to download and play whenever you wish.

@Salty: Gabe Newell has said before that in the unlikely event that Valve goes out of business, they'll release a patch that will unbind all your game purchases from Steam. You won't lose anything. <-But it is extremely unlikely this will ever happen. Valve sure isn't going anywhere anytime soon, so this should be a non-concern to anyone.

The Steam launcher is perhaps the biggest drawback of using Steam, that you must play every single game purchased through Steam from the launcher (Trying to launch the games without the launcher will NOT work.) I personally have no issues with this, as I have Steam running at all times on my computer, but some others do have a problem with this.

Just be aware of this before you begin buying games on Steam only to find out that you cannot play them without using Steam itself.

Hi There. I am a PC user who uses Steam to play all sort of games like Cs:go Mw3. This is Just like the Xbox Live Market place but here is the great part. Its Free you just create a free account and you buy games and they install on your Hardware. Just like that. Its Fun and Easy. So to Recap

Steam=Free account

Buy games= Installed to hardware

Hope this helps Gl :)

Steam is digital download service. You buy games once and get to download and play those games.

More at: http://store.steampowered.com/about