What is The difference between k and K?

Answer 1

k is the lower case and K is the upper case. Why do we say so? In olden days, in the printing press, the letters, carved at the tip of lead cuboid, were placed in wooden arrays. Small letters usually were placed in the lower case and the capital letters were in the upper case. Hence the name.

In SI system k, stands for kilo and K stands for Kelvin, the unit of temperature.

K in chemistry stands for the element, Potassium.