Sega Mega CD/Sega CD

The Sega CD, known also as Mega-CD in most regions outside North America and Brazil, is a CD-ROM accessory for the Sega Genesis produced by Sega as part of the fourth generation of video game consoles. It was released on December 12, 1991, in Japan, October 15, 1992, in North America, and April 2, 1993, in Europe. The Sega CD plays CD games and adds hardware functionality such as a faster CPU and graphic enhancements such as sprite scaling and rotation. It can also play audio CDs and CD+G discs.

Sega sought to match the capabilities of the competing PC Engine CD-ROM² System, and added an additional CPU and custom graphics chip. They partnered with JVC to design the Sega CD. Fearful of leaks, Sega refused to consult with Sega of America until the project was complete