TL;DR: Valve's Steam, which launched in 2003, became a major digital storefront by 2008, revolutionizing PC gaming. Many gamers have amassed extensive libraries, often expanded during Steam Sales.

I’ve been a PC gamer for almost two years now. Yes, it’s not a long time, and yes, I definitely hopped on the hype train a little later than most. But still, you’d think that by now I’d have a solid ...