system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Steam trading cards, gems, mystery cards, etc...

I'm so clueless.  I don't know what to do.  Turn them into gems before the end of the sale?  It's so weird and makes me uncomfortable...
gpt
**Steam Trading Cards are virtual cards earned by playing games on Steam. Sets of cards can be turned into game badges and tradable Steam community items.**

**Once you’ve collected a set of cards you can craft them into a game badge. Like the current badges, they are tied to your account and are shown on your profile. Unlike the current badges, crafting game badges earns you marketable items like emoticons, profile backgrounds, and coupons.**

**Level up your badge by collecting the set again and earning more items.**

**All badges now have XP which contributes to your Steam Level, a summary of your badge collection. You can view someone’s Steam Level by hovering over their avatar. Leveling up earns you non-tradable items like profile showcases, extra friends list slots, and more.**