[ Video & Online Games ] Open Question : Whats the difference between sega genesis pal and normal sega genesis?

I just bought this http://www.ebay.com/itm/320879055881?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649#ht_500wt_1063 on ebay and notice when you type in sega genesis quite a few different ones come up i think one plays disks and other cartridges just hoping to get the best one possible of the 2, and hopfully latest one i bought the Pal one so i dont know if i did right, just want to be able to get sonic 1-3 for it :(

Source: http://answers.yahoo.com/question/index?qid=20120401215929AA4h0aA

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