Most of the time this is a sign of a defective keyboard. Less likely possibilities would be the USB port is bad or some kind of configuration issue.
OK EXCUSE FOR WRITING IN CAPS BUT YOU SEE THIS IS THE PROBLEM. 'T' AND 'G' WON'T WORK IN LOWER CASE,
well They will BUT TYPES LIKE random leTTers and symbols (IE: ??adfgs)AND 'B' TYPES 'bc' in lower case. All oTher keys are fine. i am sure i had no spillaGe whaT could be The issue??
Thanks for readinG and any help would be GreaT.
I AM RUNNING SNOW LEOPARD ON 13in YEAR OLD MACBOOK

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic