Sega was formed from a slot machine maker and an arcade machine maker in 1964.  For two decades they focused on making arcade games until development began on the SG-1000 in 1983.  Sega released the mark III version of the console worldwide as the Sega Master System.  After it's success they began making home consoles and video games.  The company had great success early on with consoles like the MegaDrive/Genesis and its Sonic games.  Unfortunatly they released a run of consoles that were commercial failures and reverted back to being third party game developers.

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