This one comes from that greatest of Distopean science-fiction films, Paul Verhoeven's 1987 masterpiece, RoboCop.
This weapon was based on the real-life Beretta 93R, which was a development of the famous Beretta 92 pistol, in service with the US Armed Forces as the M9. The movie version is given an extended barrel and compensator/ barrel weight/ heat sink to lessen the recoil and muzzle rise of a small weapon firing a burst at a high cyclic rate. The prop masters also added a large front a rear sight set.
The real 93R is a select-fire pistol chambered in 9x19mm NATO round and firing from a 20 round detachable box magazine. Unlike the 92, the 93R is a single action pistol. The "R" stands for Raffica which translates to "burst" in Italian. There are two modes of fire, semi-automatic and burst. The burst is of three rounds, firing at approximately 1100 rounds per minute. The designers opted for a burst mode rather than a true full automatic to help minimize muzzle rise and its attendant ammunition wastage.