This is not really a homework question, I am sorry, but I didn't know where to find this information on the website or Google.

This is not really a homework question, I am sorry, but I didn't know where to find this information on the website or Google. I am wondering if you can tell me a little more about the group flash cards? I have some study partners in a class with me and I like to make flash cars. It says something about seeing the stats of everyone in the group... Is it like a game, or a challenge, or leaderboard, etc? Please elaborate so my friends can decide if they want to make an account.