Sonic the Hedgehog CD

, or , is a platform video game developed by Sonic Team and published by Sega originally for the Sega/Mega-CD in 1993. It is the first game in the Sonic series to make use of the CD-ROM format, featuring high quality audio and full motion video. Development began in Japan around the same time as Sonic the Hedgehog 2 in the United States. Originally, the games had many similarities, but over time became vastly different projects.