Something that always bothered me about HDD size abbreviations (GB, GiB etc.)
The SI prefix "giga-" abbreviated "G" means 10 to the ninth power. A gigameter is a billion meters. A gigasecond is a billion seconds. A gigabyte is a billion bytes. Period.
Computer scientists are the ones are misusing the established terminology, and there's an obvious reason for it but it's still the cause of a lot of confusion. Most computer memory is addressed in ranges that are nice, neat multiples of two. A 10-bit address range lets you access 1024 different addresses. It was convenient to call it a kilobyte because it was close to the SI prefix kilo- meaning 10 to the third power. They were only 2.4% different, so it was good enough.
Unfortunately approximating a megabyte as 2 to the 20th is more inaccurate still: it's 4.85% larger than a million bytes. 2 to the 30th is an even shoddier approximation of a gigabyte at 7.37% larger. At terabyte scales we're very nearly 10% larger! The situation is bad enough that there are actually formalized SI prefixes for the binary approximations. Your hard drive really is 40GB, but it's also 37GiB (pronounced "gibibytes" where the "bi" stands for binary.) When are computer OSes gonna start using the right measure of units?
The SI prefix "giga-" abbreviated "G" means 10 to the ninth power. A gigameter is a billion meters. A gigasecond is a billion seconds. A gigabyte is a billion bytes. Period.
Computer scientists are the ones are misusing the established terminology, and there's an obvious reason for it but it's still the cause of a lot of confusion. Most computer memory is addressed in ranges that are nice, neat multiples of two. A 10-bit address range lets you access 1024 different addresses. It was convenient to call it a kilobyte because it was close to the SI prefix kilo- meaning 10 to the third power. They were only 2.4% different, so it was good enough.
Unfortunately approximating a megabyte as 2 to the 20th is more inaccurate still: it's 4.85% larger than a million bytes. 2 to the 30th is an even shoddier approximation of a gigabyte at 7.37% larger. At terabyte scales we're very nearly 10% larger! The situation is bad enough that there are actually formalized SI prefixes for the binary approximations. Your hard drive really is 40GB, but it's also 37GiB (pronounced "gibibytes" where the "bi" stands for binary.) When are computer OSes gonna start using the right measure of units?
