When you search for something you may have seen the expandable grid box on Google that containing a series of questions. They are the "People Also Ask" PAA boxes in Google's SERPs. These are the questions that related to your search. Why PAAs are important? Research has found that a single PAA question can show up in 21 unique SERP results which mean If you have PAA question in your content there are chances for your content to appear in 21 unique SERP results.

Check out this link to learn more about PAAs: https://bit.ly/2mzqkUY