A featured snippet is a box at the top of some search results where Google lifts a direct answer to the query from a web page, displaying it above the regular organic listings, sometimes called position zero.
A featured snippet sits above everything else. Earning one puts a small business ahead of competitors who rank in the normal positions, including ones with bigger sites.
It works for question-style searches. The snippet is Google's answer to a what, how, why or definition query, so content built to answer those questions clearly has a real shot at the box.
It builds authority even without a click. Some people read the snippet and move on, but your business name is the one shown answering the question, which is its own kind of visibility.
A plumber writes a clear, well-structured page answering how long does a hot water system last, with the direct answer in a tight opening paragraph.
Google lifts that paragraph into a featured snippet for the query, putting the plumber's page above every other result.
People researching a failing hot water system see the plumber answering the question authoritatively, and the plumber's name is the one in front of them when they decide it is time to call someone.
In-House structures content to be snippet-eligible through the content and SEO agents: tight definitions, clear question-and-answer formatting, and the schema that helps Google parse it.