what are semantic tags in html

Question

semantic tags in general

Answer 1

It means that they have a meaning.
I.e. <nav> for the navbar. Or <aside> for the sidebar.
But you could also use <div> for a navbar or sidebar, but the word "div" is just a container without a specific meaning and therefore not semantic.

Here you can see a list of semantic elements: https://www.w3schools.com/html/html5_semantic_elements.asp

Answer 2

Nav, aside, footer, header