what does pt and em stand for in text-indent property ?

Question

I studied on SoloLearn that the value under text-indent property can be in terms of cm, px pt and em , i know what px and cm stands for ,but not sure what does pt and. em mean .

Answer 1

https://youtu.be/2CW2B7W4Vas

See this

Answer 2

pt stands for POINTS
and em stands for (emphemeral unit) which is used for font size.
for example : 3em, that means 3 times the size of the current font.