JavaScript
From User talk:Rua
Here are some users who know JavaScript: User:Kephir, User:Dixtosa, User:WScriptBotish, User:This, that and the other, User:Jberkel, User:Sae1962, User:Brantmeierz, User:RayZa, User:Im.mers.io, User:Thomas James Foster, and possibly also User:Hippietrail.