Such PAA or People Also Ask feature is one series of dynamically loading questions which are related to the first searched query showing in those search results on the mobile and desktop. If a user would click on a certain question in such PAA feature, such drop-down would appear with those featured snippets known as the quick answers from a different search result.
For various PAA results, each time the user clicks an extra PAA question, then such new dynamically loading question is going to appear below. Also, there have also been some instances of a lot of PAAs but there are more that stop after a series of new questions. Such PAA feature first showed in the search results in the summer time of 2015. Know that the organic search feature is actually part of the ongoing efforts of Google for improving the search experience and also keep those searches in the Google interface much longer.
Know that unlike such featured snippets, the People Also Ask feature is certainly moving around the first page of these result pages. But, so many of the PAAs actually appeared below the first search result page.
There had been that increase in popularity of the People Also Ask feature when Google put this in 2015. You should learn that the PAA is actually one of the fastest growing search result page features and is also much faster even those featured snippets also called the quick answers.
What you should know is that such PAAs actually show in 70 percent of the search results that show snippet and this seems to be using the same source for answering the featured snippets and the different PAA questions. What this truly means is that ranking the answer to such featured snippet as well as PAA question may result in various instances of exposure. An info that you must know is that one PAA may show up in more than 20 search result pages.
If you try to rank like the answer in People Also Ask question, you have to optimize in the same way like how you would for that featured snippet. Make sure that you answer the question in a very concise, clear and in such authoritative manner. Having that question or answer to content would give a much better experience for the user by aligning the intent of the user with the relevant content.
It would be great that you go through the website so that you will be able to get more info on the benefits of Google expanding the People Also Ask feature. With this, you can learn more on how you can benefit using the PAA.