My introduction to TF2 is a pretty long explaination, but I think I can still do it.
So, one year ago, I was just a gaming addict 12-year-old. I still am, but that's besides the point. I wanted to play on a platform where I could play as many games as I want without leaving the platform, much like Nintendo or an Xbox. So, I started on Steam. A few months later, my friend started to play this game called Team Fortress 2. I thought it was boring, so I just continued to play the usual game I played (I don't play anymore..): Minecraft. A few weeks later, I started to play TF2, just because Minecraft started to get boring. I found out that TF2 was a great game to play on, even though I sucked... I couldn't even snipe a standing heavy. Later on, my friend quit, and moved to Garry's Mod & CS:GO (Obviously I play CS:GO too), right when I started to get good. I started to put money into the game (about 400-500$), yet my backpack isn't nearly as much as that.. I guess I should stop unboxing. My backpack was @ 40$ after uncrating. It was sad. But then, I started to work my way up to about 150$, just by trading and getting my friend's backpack (his was also 40$, yet he spent 100$).
That is my story of getting into the world of Team Fortress 2.