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1.
(Comp Sci.)
Equal to 1,048,576 bits, though commonly referred to as one million bits. Abbreviated as mb.

mB = Megabyte
mb = Megabit
Examples:

mBps (Megabytes Per Second)
mbps (Megabits Per Second)
I downloaded at 6mbps.
Which is approximately 6,291,456 bits.
by VoiDeD May 01, 2005
9 1