Here at the Chad’s News network command center, we have long been aware of the difference between the hard disk capacity reported in decimal bytes by the manufacturer and the the same capacity reported in binary bytes by Windows. In fact, I was once published in a print magazine after the editors incorrectly answered a question on the subject.
Most computer programmers and system engineers already know why one kilobyte (KB) can either be 1000 or 1024 bytes, and the more experienced ones know that a kibibyte (KiB) is always 1024. For others, the linked article explains all. I found the most useful part of the article to be Tables E and F, which list the measurement type used for various protocols and computer components.