How much is a megabyte? Most people would probably say 1 million bytes. Nerdy people would probably say 2^10 bytes, or 1,048,576 bytes. You know what I found out recently? The first is correct. At least according to the SI standards. That page says IEEE has adopted this standard also. 2^10 bytes (which I believe Windows uses as a megabyte) is a mebibyte. You learn something new every day.