Mega CD

The Sega Mega CD was an add-on device for the Sega Mega Drive released in Europe, Australia, New Zealand and Japan in 1991. Initially, it was a great success because of the inherent advantages of CDs (high storage capacity and the low cost of media). Despite having been on sale for over two years, by March 1994 the MEGA CD had only sold 380,000 units in Japan, which meant that only a limited number of Japanese Mega Drive owners had purchased the add-on unit. Sega of Japan did not inform Sega of America about their Mega CD plans for that market until a few months later.

The Genesis add-on for the North American market was known as the Sega CD. This device allowed the user to play games, audio CDs, and CD+G discs. The development of the Mega-CD was confidential; game developers were not made aware of what exactly they were working on until the add-on was finally revealed at the Tokyo Toy Show, in Japan. The Sega Mega CD was designed to compete with the PC Engine in Japan, which had a separate CD-ROM drive.

The Sega Mega-CD was not meant to compete with the Super Famicom (Super Nintendo Entertainment System outside Japan). This posed a problem in the markets outside of Japan, where the PC Engine did not fare very well, and the expectation was that the Mega-CD would be in competition with Nintendo.