What is Kelvin?

Kelvin is, or relates to, a unit increment of temperature known as the kelvin (symbol: K). The kelvin is the SI unit of temperature and is one of the seven SI base units. The Kelvin scale is a thermodynamic (absolute) temperature scale where absolute zero—the lowest possible temperature where nothing could be colder and no heat energy remains in a substance—is defined as being equivalent to zero kelvin (0 K).