CSS Combinators: it is something that explains the relationship between the selectors.

A Css selectors can contain more than one simple selector.

there are 4 types of combinators:

Descendant Selector

they matches all the elements that are Descendant of a specified element

paragraph 1 in div

paragraph 2 in div

paragraph 3 in div

paragraph 4 not in div

paragraph 5 not in div