Mark is a fictional character played by Jeffrey Muller in the television series The Office. He was Jim's room mate until Jim moved to Stamford. It is unclear whether Jim moved back in with Mark after returning to Scranton in The Merger.
Season 2: Edit
Mark is Jim's roommate who was very interested in meeting Jim's co-workers based on the stories he has heard. He was especially interested in meeting Dwight because he didn't believe that Dwight could be real. Mark was very impressed when he met Dwight and realized that Jim was telling the truth. He has a girlfriend but her name is not mentioned.