A megabyte is a unit of information or computer storage equal to either 106 (1,000,000) bytes or 220 (1,048,576) bytes, epending on context. In rare cases, it is used to mean 1000×1024 (1,024,000) bytes. It is commonly abbreviated as Mbyte or MB (compare Mb, for the megabit). The term megabyte was coined in 1970.