I might be a bit rusty but... It was an animated series that revolved around four kids helping an AI in a supercomputer that's in some abandoned building. While the 'nerd' of the group helps from outside and the other three enter it through theses virtualization pods in a secret room. When in the virtual world the kids also get these costumes that give them combative tools/abilities. The main mission being to help fight some malicious force that is trying to take over the computer (and get out).