It is a feature of Google. Google Map pack is an enhanced search feature that displays results of searches in maps that include business listings, appearing above traditional blue-link organic results in Google. Ranking in it isn't easy and its appearance depends on a variety of factors, however you can apply best practices to improve local SEO and increase chances of appearing in it for terms relevant to search.
Google considers a variety meaning of seo in digital marketing (sixn.net) aspects when deciding on which businesses should appear in its Map pack, such as reviews and claims made on listings, the degree to which they are optimized the website of a company as well as Google Business Profile are, among others.
As being featured in the Map pack, it can boost phone calls, foot traffic and overall business growth for your company, it also gives your brand the chance to grow its reputation while giving its competitors an edge who don't rank.