Rich Snippets are the more enhanced search listings that Google displays on search results pages. Additional data and formatting create a “richer” experience tailored to answering the user intent more efficiently. This can be lists, images, reviews, product information, videos and more as Google is constantly experimenting.
Having a rich snippet can increase the click-through rate to your site as they grab attention and show expertise/validity on the subject matter.
There’s no hard and fast way to guarantee a rich snippet for your site, but creating high-quality and well-formatted content is one of the most helpful things you can do. Furthermore, appropriate use of structured data can help Google understand the information on your page more easily, which can help gain rich snippets.