Pretty much the same thing as the Sega SG 1000 but with extra RAM, keyboard, and extra hook ups for things like disk drive, tape drive etc. The insides are basically a MSX computer (which made it more powerful than it's biggest competitor, the Nintendo Famicom.) Has some unique games on tape that the SG 1000 doesn't have. All software for this console is backwards compatible with the SG 1000 machine, with the exception of Music and Basic programs. A keyboard was also made for the SG 1000 to allow it to function like a computer. Has some unique add-ons like a light pen and voice synthesis module. There is also a "SG 3000H" with a proper keyboard (a normal one as opposed to a membrane keyboard) and more ram. Funny story: This console was exported to the rest of the world as the Sega Master System, then re-imported back to Japan as the Master System 1. Pretty hard to find today