Why did you join Steam?

To buy TF2 for a friend as a Christmas present. After that the Valve Complete Pack went on sale for $25 so I got it and got used to using steam.

Deus Ex.

A friend of mine was playing CS1.6, so I wanted to join in on the fun. I was pretty bad, but that didn't stop me from playing that all the time.
Fun fact: I still suck at most games. It seems most of my game-suckery is due to my insane levels of tunnel-vision and lack of deliberation whilst playing. Mostly, I just react.

I joined steam because. My brother got half life 2 and it required steam, So he made a steam account and played half-life 2 on my mother's computer.I found out about garry's mod 9 and played it on my bro's account Then my brother got orange box to play garry's mod 10 then i got orange box to play garry's mod with him. I kinda took over my brother's steam account so my brother made a new one.

I joined to play L4D2.

TF2 free to play

I started Steam right around the time I started college (since I finally had interent access from a house I was living in, not from a library for about two hours). One of my friends convinced me to get Steam, and I did so on September 1st. Didn't really do much with it until Humble Bundle for Android 4 came out in October. The rest, as they say, is history.

Because the stores in my town sell nothing besides the newest AAA shit titles and about 20 different kinds of The Sims games and nothing else.

My friends were really into TF2 at the time, and I knew they used to be into CS:S for a while. Both were on steam.

Got a free copy of Mafia II with my video card.

bought portal 1 in stores when it came out

i wanted to buy MW3, it was about $100 at a local store (i didnt know that it is a steamworks game at that time) so i decided to buy it on Steam (full price yey, also didnt know about sales).

they were giving away free portal! FREE PORTAL!

To play CS:S with friends from school.

Because Xseed announced Ys Origin would come to Steam and I wanted it.

Because Valve was giving away Portal for free

When Gamespy offered Fallout New Vegas free with purchase of Brink. So yes. Brink is what brought me to steam.

My brother told me about it...I was a console only gamer until that time. My steam library started off slow, then it started to grow!

My friend shamelessly promoted Steam and forced me to play with him. =x

Terraria was the game that introduced me to Steam if I remember correctly, let's have a look!

Yups, Terraria was my first purchase on Steam. It was also my first giveaway on SteamGifts, fancy that.

Not orange box, but bought some 3-pack including css. Wanted to play css.

I'm not exactly sure... XD

I was kind of sick of the whole "unpack, burn and mount" nonsense only to have the torrents only work about half the time and there was a big sale going on.