Curve is an electronic shop from Grand Theft Auto: Liberty City Stories and Grand Theft Auto: Vice City Stories. In GTA Liberty City Stories, a store can be found in the shopping mall at Belleville Park, Staunton Island. In GTA Vice City Stories, there are three stores located in Ocean Beach, Downtown and Little Havana. The company apparently manufactures electronics, as a billboard advertising a Curve car stereo can be seen in GTA Liberty City Stories. Also, the company's logo can be found on Yankees in Vice City Stories.
Evidently, Curve has left Vice City by 1986, as there are no Curve stores in Grand Theft Auto: Vice City.
The logo of Curve bears much resemblance to the computer manufacturing company IBM.
The name Curve actually means whores in Romanian, so this may be another Rockstar joke.