Coding Games

What programming language is used to code games in correspondence sites like LG, BAJ, SuperDuper, BGA, etc.? I am very much a novice when it comes to coding, so if the nature of my question flawed, let me know. I would love get into coding some very basic games as a hobby, and was curious what is used to create these sites I love.

Appreciate your help.

I'm fairly sure that LG backend is written in Java.

BGA offers a coder-friendly environment. They won't teach you the languages needed, but you can find and access that information on your own, for free.