The Mega CD, or in North America, the Sega CD, was an add on for the Sega Mega Drive, manufactured by Sega. There were two models of the Sega Mega CD released, the Model 1, and the Model 2. It was released in: Japan: December 12, 1991 Europe: April, 1993 North America: October 15, 1992 Australia: April, 1993. The console sold over six million units, and had moderate success.
Nintendo's Super Nintendo Entertainment System (SNES) was taking over market share and sales over Sega's Mega Drive / Genesis. Sega wanted to spike more sales of the Mega Drive, and development began on the Mega CD. Developers working on launch titles didn't know what hardware they were programming for until the Sega Mega CD was officially announced.
The Sega Mega CD was released in two models. The first model was an add on that plugged into the side expansion port of the Mega Drive, and was designed to sit under the Model 1 Mega Drive, and matched the design of the Model 1. It had a disc tray that slid out of the front of the add on, making it a frontloader, activated by the use of a button. The Model 2 Sega Mega CD was made to fit with the Model 2 Sega Mega Drive. The add on had the CD section on the right hand side, and the Mega Drive sat on the left. The Model II Mega Drive matches the design cues of the Model II Sega Mega CD. It had a button to open the CD tray, with a simpler mechanism than the Model I, and the Model II was a toploader. Both Mega Drives (The Model I and Model II) were compatible with both Models of the Sega Mega CD, except the Genesis 3.
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