when i should use px, pt, cm, mm ?

Question

when i should use px, pt, cm, mm ? what is different case of using this ?

Answer 1

In most of cases forgot mm or cm just use px or pt. Anyway pt is better for writing for layout independent on real size of screen - while 1 px is always 1 px, 1 pt can be 2px dependent on screen.

Answer 2

Use absolute length (mm, cm, pt) units when creating layout for printer.
When displaying on screen, relative units (em, rem, vh, vw) are better.
Generally avoid using px. On most of today screens (FullHD or 4K) it doesn't represent 1 pixel

Answer 3

is cursors