 The prefixes for data units, such as bits and bytes, will work a little differently than those that we saw for things like meters and seconds. First of all, we won't have to worry about small units. We can't have fractions of a bit, so we won't have any millibits or nanobytes to worry about. We also won't worry about DECO or HECTO. Instead, we'll focus on the larger powers. But there's some confusion here. In general, we don't use powers of 1,000 now. For example, a kilometer is 1,000 meters. A kilo-second would be 1,000 seconds, but generally when we're working with bits and bytes, we use scales of 1,024. So a kilobyte is 1,024 bytes. A megabyte is 1,024 squared bytes, which would be 1,048,576 bytes. This is the general convention for scales for data units, but it's not completely universal. Storage manufacturers and ISPs have traditionally quoted their products on scales of 1,000. To get around any potential confusion, they usually also have a disclaimer at the bottom of the packaging or the ad saying that, say, 1 gigabyte is 1 billion bytes. Most computers, though, do use the 1,024 to 1 scale. Apple, since 2009, has been the exception here where they do use the 1,001. It doesn't really change how much storage or bandwidth you have, it just changes how you look at it. Devices now seem larger on a 1,001 scale than they do on a 1,024 to 1 scale. But most operating systems have still stuck with the 1,024 to 1. This led the IEC, International Electrotechnical Commission, to come up with some new nomenclature back in 1998. So now instead of having kilobytes as being 1,024 bytes, a kilobyte could be 1,000 bytes as you would expect, but our computers could report a kibby byte being 1,024 bytes. While this system has been around since 1998, it took about 15 years before it started seeing any real use. It's still not terribly common, but you'll see it once in a while. The main distinguishing feature is that they stick this tiny I after the main unit. Now we have a different pronunciation, which is a little bit harder to say, but it's still representing the same concepts that we're used to. For the moment, though, most systems still use 1,024 to 1, and they still describe those as being megabits or terabytes. But we're using a base of 1,024, so we do get some discrepancy when we start getting larger numbers. It's not too big when you're looking at small things like kilobytes or megabytes. Once you start getting larger units like terabytes and petabytes, there can actually be some pretty big discrepancies there.