About Kelvin
Kelvin is an absolute temperature measurement defined in the International System of Units (SI). It is named after the Scottish physicist William Thomson (Lord Kelvin) who studied the field of thermodynamics. The Kelvin scale is based on absolute zero; the point at which all molecular motion ceases.
Unlike most other temperature scales, Kelvin does not have degrees as it is not a relative scale. The Kelvin scale is often used in physics, chemistry, and cosmology.
One advantage of Kelvin is that it does not have negative values making some calculations easier. This is useful in science calculations involving gases as it relates to the kinetic energy of molecules.
About Newton (temperature scale)
The Newton scale is a temperature scale that is now obsolete.
On the Newton scale the zero point is the freezing point of water and 33 degrees is the boiling point. This means that each degree on the Newton scale is significantly larger than a degree on the Celsius or Fahrenheit scales.
The Newton scale has been consigned to the history books but may be referenced in some (very) old textbooks.