What font units do you use?

Question

css

Hello. I used to always set the font size in pixels, but then I came across a project where 90% of all font sizes are set in em and the rest in vw.
What are the benefits of this approach? So I came to the project with a new front, it’s not immediately clear what is hidden behind these numbers, but on the layouts there are quite clear sizes, for example 16px.
What font units do you use?

Answer 1

Advantages in relativity.
It is enough to change the font at the root and it will change everywhere.
Lacks in obscurity. For now, rem
should be used for these purposes , leaving em only where it is really convenient. I use px myself and keep postponing the transition to rem .)