We will be adding various kinds of stickers in the future, but started off with some basic ones. Any suggestions are welcome if you'd like to see one added.
I've always enjoyed playing games and sites that have this kind of functionality. One notable site is Stack Overflow with their Badges. Some time ago, I played World of Warcraft and they had Achievements. Working towards something was always fun and wanted to bring the same kind of fun to Drifting Ruby.
Why the name?
Many sites have this kind of functionality. They all coin their own naming of these kinds of "badges". However, I wanted something unique and didn't like the term "Achievements". Some other thoughts were Rewards, Trophies, However, some of these terms felt like some may find it as a false sense of accomplishment. So, after some time, we came up with Stickers. After all, who doesn't like stickers.