Kb one thousand twenty four bytes.  see byte and Kilo-

Kbps ( kilobits per second ) A measure of bandwidth (the amount of data that can flow in a given time).  Kbps is defined as the number of bits per second ( in thousands ) that can be transmitted over the specified data transmission medium.

kHz (kilohertz) abbreviated kHz or KHz*, kilohertz is a unit used to measure the frequency of  alternating current (AC) or an electromagnetic (EM) wave.  It is defined as one thousand hertz (One thousand (1,000) cycles per second). ( Note: * The engineer's society, IEEE, and most other sources prefer "kHz" to "KHz." This apparently makes it less likely that users will confuse "kilo" (decimal 1,000) with the computer "K" (1,024). )

kilo- Abbreviated k (always lower-case). A prefix signifying one thousand (10E3).

Kilo- Abbreviated K (always upper-case). A prefix used in computer work to signify multiples of 1024 (i.e., 2E10). Meant to distinguish base-2 (binary) from base-10 (decimal) magnitudes. For example, a "16K" memory is actually 16,384 bits (i.e., 16 times 1024, or 2E14).