MBps = megabytes
Mbps = megabits
So, if you refer to my speed test above you will see that I am getting 11.53 Mbps per second. To find out how many megabytes that is you just divide by 8 which equals 1.44 MBps.
Now, 1 MB is equal to 1024 KB (kilobytes) so if you want to know how fast you are going to able to download a song or movie you should refer to the KB or MB per second rate as that is usually what they are measured in.
For example, if you are downloading a 50 MB file at 1 MB per second it will take you just under 50 seconds. Got it?