Kelvin, a unit of thermodynamic temperature, is defined as the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. It forms the basis of the absolute temperature scale, where zero represents the absence of all thermal energy. A temperature difference of one kelvin is equivalent to a difference of one degree Celsius. For instance, 293.15 kelvin corresponds to 20 degrees Celsius.
The adoption of this absolute temperature scale is crucial for scientific calculations and comparisons. It provides a consistent and unambiguous reference point, unlike Celsius or Fahrenheit which are based on arbitrary zero points. Named after William Thomson, 1st Baron Kelvin, who proposed it in the mid-19th century, this unit is fundamental to various fields, including physics, chemistry, and engineering, enabling accurate measurement and analysis of thermal phenomena. Its use simplifies many thermodynamic equations and facilitates a deeper understanding of temperature-dependent processes.