Kilometre per hour (Metric), speed
Kilometres per hour (American English: kilometers per hour) is a unit of both speed (scalar) and velocity (vector). The unit symbol is km/h or km·h−1. The incorrect abbreviations "kph" and "kmph" are sometimes also seen in English-speaking countries, in analogy to mph. In North American slang and military usage, km/h (as well as km) is commonly pronounced, and sometimes even written, as klicks or kays (K's).