A bunk bed was a type of bed. In starships, they were usually built into the wall as an alcove, usually in pairs, with one bed on top and the other below. Each alcove often featured sliding doors to afford the occupant more privacy if desired. More traditional bunk beds were freestanding units.
In 2293, the USS Excelsior had freestanding bunk beds in use in common quarters, allowing at least four officers to share quarters. Tuvok slept in a bottom bunk. (VOY: "Flashback")
In 2371, Quark complained about his accommodations on the USS Defiant, which included bunk beds. (DS9: "The Search, Part I")
Soon after, Julian Bashir offered Jadzia Dax the top bunk in his quarters while staying on Trill, but she declined, preferring the bottom bunk due to Curzon Dax's once having fallen out of a tree. (DS9: "Equilibrium") The USS Enterprise-D was shown to have freestanding bunk beds in use during this year. (Star Trek Generations)
Junior officers aboard the USS Cerritos slept in bunk beds built into the corridor walls. (LD: "Second Contact") In 2380, Ensign Beckett Mariner's assigned bunk was number A12001 (LD: "Envoys"); Sam Rutherford's bunk was A12002 (LD: "Moist Vessel"); Brad Boimler's bunk was A12003. (LD: "Temporal Edict") These bunks were located at Deck 11 on the USS Cerritos. Each duty shift was berthed in a separate corridor. (LD: "Terminal Provocations")
In 2383, the USS Protostar featured a bunk room that was meant to berth much of the ship's crew in bunk beds, arranged in a pattern in the center of the room and secured to the deck. (PRO: "Starstruck")
Kestra Troi-Riker's room in her parents' house on Nepenthe featured a bunk bed. Soji Asha slept in the bottom bunk during her stay at the house in 2399. (PIC: "Nepenthe")
Retired Admiral Jean-Luc Picard and Captain William T. Riker were both assigned to the same quarters with bunk beds on the USS Titan-A as a demonstration by Captain Liam Shaw that he was in command of his own ship. (PIC: "The Next Generation")
