Kilobyte
参考wiki的解析
1 kB = 1000bytes = 103 bytes is the definition recommended by the International Electrotechnical Commission (IEC).[6] This definition is used in networking contexts and most storage media, particularly hard drives, Flash-based storage,[7] and DVDs, and is also consistent with the other uses of the SI prefix in computing, such as CPU clock speeds or measures of performance. The Mac OS X 10.6 file manager is a notable example of this usage in software. Since Snow Leopard, file sizes are reported in decimal units.[8]
注意1MB就是2^20Bytes 是大于1000KB的，其实是1024KB才对 1GB 2^30Bytes
1 KB (or KiB) = 1024bytes = 210 bytes is the definition used by most vendors of memory devices and software when referring to amounts of computer memory, such as Microsoft Windows and Linux.[9] In the unambiguous IEC standard the unit for this amount of information is one kibibyte (KiB).
操作系统和内存中，是使用KB做单位的，简写为K。
kk@gentoo /tmp $ ls -l OpenHardwareMonitor.zip
-rw-r--r-- 1 kk kk 367415 2014-06-07 12:08 OpenHardwareMonitor.zip
kk@gentoo /tmp $ ls -lh OpenHardwareMonitor.zip
-rw-r--r-- 1 kk kk 359K 2014-06-07 12:08 OpenHardwareMonitor.zip
稍稍注意的是应用例如split来截取数据，其中split的 -b KB 和 -b kB 是一样的，都是只 -b kB, 而 -b -K 就是截取 KB了。
kk@gentoo /tmp $ split -b 100kB OpenHardwareMonitor.zip OpenHardwareMonitor
kk@gentoo /tmp $ ls -lh OpenHardwareMonitor*
-rw-r--r-- 1 kk kk 98K 2014-06-07 12:30 OpenHardwareMonitoraa
-rw-r--r-- 1 kk kk 98K 2014-06-07 12:30 OpenHardwareMonitorab
-rw-r--r-- 1 kk kk 98K 2014-06-07 12:30 OpenHardwareMonitorac
-rw-r--r-- 1 kk kk 66K 2014-06-07 12:30 OpenHardwareMonitorad
-rw-r--r-- 1 kk kk 359K 2014-06-07 12:08 OpenHardwareMonitor.zip
kk@gentoo /tmp $ ls -l OpenHardwareMonitor*
-rw-r--r-- 1 kk kk 100000 2014-06-07 12:30 OpenHardwareMonitoraa
-rw-r--r-- 1 kk kk 100000 2014-06-07 12:30 OpenHardwareMonitorab
-rw-r--r-- 1 kk kk 100000 2014-06-07 12:30 OpenHardwareMonitorac
-rw-r--r-- 1 kk kk 67415 2014-06-07 12:30 OpenHardwareMonitorad
-rw-r--r-- 1 kk kk 367415 2014-06-07 12:08 OpenHardwareMonitor.zip
kk@gentoo /tmp $ rm OpenHardwareMonitora*
kk@gentoo /tmp $ split -b 100K OpenHardwareMonitor.zip OpenHardwareMonitor
kk@gentoo /tmp $ ls -l OpenHardwareMonitor*
-rw-r--r-- 1 kk kk 102400 2014-06-07 12:31 OpenHardwareMonitoraa
-rw-r--r-- 1 kk kk 102400 2014-06-07 12:31 OpenHardwareMonitorab
-rw-r--r-- 1 kk kk 102400 2014-06-07 12:31 OpenHardwareMonitorac
-rw-r--r-- 1 kk kk 60215 2014-06-07 12:31 OpenHardwareMonitorad
-rw-r--r-- 1 kk kk 367415 2014-06-07 12:08 OpenHardwareMonitor.zip