1K

1K has several uses including:

*As a quantity 1 K means 1 kelvin. [http://www.bipm.org/en/si/si_brochure/chapter2/2-1/kelvin.html]
*As a number 1K refers to 1000, or 1024, as a kilobyte.
*Southern Cross Distribution IATA code
*Sutra IATA code
*A term to describe Digital cinema
*A term to describe an elite membership level of United Airlines' Mileage Plus program