I have been using smokeless tobacco on and off for years. I thought I quit numerous times but I now realize that wasn't really the case. You can say that I merely stopped using for periods of time. The difference now is that I finally quit, meaning that I am done and will not start again. I'm well over the hump.
A megabyte is one thousand times larger than a kilobyte. The prefixes mega- and kilo- are used by a metric system of counting which is based on powers of ten. Mega comes from a Greek word megas, which translates as great. In metric systems, mega- denotes one million.
MB is larger. There are 1024 KB in a MB. MB are bigger, just like GB are bigger than MB. Just think of Kilo being small, Mega being large, and Giga being huge, and then there is TB, but I won't get into that right now.