Pages like pokemonshowdown.com/users/sumwun list the user's ratings in various formats. All the formats seem to be categorized into either "official ladder" or "unofficial ladder". What's the difference between the two?
I believe "Official Ladder" consists of official tiers such as Ubers, OU, UU etc when they are fully set in stone and out of alpha/beta. The "Unofficial Ladder" consists of mostly other formats/metas such as monotype, 1v1, an official tier will only fall into this catagory if it's under a suspect test or still in alpha/beta.