On Federation starships, the master systems display (abbreviated MSD), also known as the master situation monitor, or master situational display, is a large, wall-mounted computer display in engineering and on the bridge. The display featured a large cutaway diagram of the vessel, and was used to provide a detailed overview of the ship's status.
The USS Enterprise-D had its master systems display in engineering, while the starships USS Voyager, USS Defiant, and USS Enterprise-E all featured their displays on the bridge. MSDs for Constitution-class starships could be loaded up from the computer.
- The first MSD was created for the sets of the Enterprise-D. According to the Star Trek Encyclopedia, it included a number of in-jokes, including "the official USS Enterprise duck, the ship's mouse, a Porsche, a DC-3 airplane, the Nomad space probe, and the hamster on a treadmill that was alleged to be the true source of power for the ship's warp engines." The only major series starships that hasn't had a large MSD of some sort is the Enterprise NX-01.