What’s a Gibi-byte?

Hard drive space actually comes in 1024 byte “blocks”, and the correct prefixes are ones like kibi-, mebi- and giba- (versus kilo-, mega-, and giga-, all of which are units of a 1000). So a GiB is simply the accurate and slightly larger cousin of the Gigabyte (1 Gibibyte = 1.073741824 Gigabytes).