Stay hungry,Stay foolish




ISQ - International System of Quantities 国际量制。以长度、质量、时间、电流、热力学温度、物质的量和发光强度七个基本量为基础的量制

SI - International System of Units 国际单位制造。由国际计量大会(CGPM)批准采用的基于国际量制的单位制,包括单位名称和符号、词头名称和符号及其使用规则。


IEC - International Electrotechnical Commission 国际电工委员会

IEEE - Institute of Electrical and Electronic Engineers 电气与电子工程师协会

1000 1024



  • 10进制的SI/ISQ
    • 10的3次方 1000
  • 2进制的IEC/IEEE
    • 2的10次方 1024
    • 词头 kibi- mebi- gibi- tebi- pebi- exbi-

bit = b = 比特

byte = B = 字节

8b = 1B

1000B = 1KB

1024B = 1KiB

Most computer hardware uses SI prefixes[defn. 1] to state capacity and define other performance parameters such as data rate. Main and cache memories are notable exceptions.

大多数计算机硬件使用的SI前缀(1000),Main and cache memories除外

Some operating systems and other software continue to use the customary binary prefixes in displays of memory, disk storage capacity, and file size, but SI prefixes[defn. 1] in other areas such as network communication speeds and processor speeds.

一些操作系统沿用2进制显示内存、磁盘、文件的大小; 网络传输/CPU速度等其它可都认为使用的10进制前缀

如需严格的单位换算,要区分好b B KB KiB

Operating systems

Prior to the release of Macintosh System Software (1984), file sizes were typically reported by the operating system without any prefixes.[citation needed] Today, most operating systems report file sizes with prefixes.

The Linux kernel uses binary prefixes when booting up.[91][92] However, many Unix-like system utilities, such as the ls command, use powers of 1024 indicated as K/M (customary binary prefixes) if called with the ‘‘-h’’ option or give the exact value in bytes otherwise. The GNU versions will also use powers of 10 indicated with k/M if called with the ‘‘--si’’ option.
The Ubuntu Linux distribution uses the IEC prefixes for base-2 numbers as of the 10.10 release.[93][94]
Microsoft Windows reports file sizes and disk device capacities using the customary binary prefixes or, in a "Properties" dialog, using the exact value in bytes.
Since Mac OS X Snow Leopard, (version 10.6), Apple's Mac OS X reports sizes using SI decimal prefixes (1 MB = 1000000 bytes).[95][96]


wiki Binary_prefix
wiki Data-rate units
《国际计量学词汇— 基础和通用概念及相关术语》