Why use em?

[Il Domandatore]

On w3schools.com it's suggested use em instead of px because first it's relative and second it's static.

I'm still confused; which is the improvement?

[dsonesuk]

It styles to current body set font size, so if you increase/decrease body font size it should style proportionately, while px remains static on font size change.

[Il Domandatore]

Do you mean when we use zoom from our browser to resize page?

[dsonesuk]

No when you increase font size; its relative to size of font.

[Sherin]

The key value em units offer is they allow sizing values to be determined by a font size other than that of the html element. For this reason, the primary purpose of em units should be to allow for scalability within the context of a specific design element

[Ingolme]

19 hours ago, Sherin said:

The key value em units offer is they allow sizing values to be determined by a font size other than that of the html element. For this reason, the primary purpose of em units should be to allow for scalability within the context of a specific design element

Source: https://webdesign.tutsplus.com/tutorials/comprehensive-guide-when-to-use-em-vs-rem--cms-23984