Google Authorship Markup is a way to connect authors with their content on the web. It allows websites to link their content to author pages, which describe and identify the author and can include the author's biography, photo, articles and more. The Markup uses standards as HTML5 (rel="author") and XFN (rel="me") to enable search engines and other web services to identify works by the same author across the web.
Advantages for a business
Unfortunately, Google abandoned the Authorship Markup, claiming that they wanted to create a better mobile experience, and because of that, they simplified the way authorship is shown in mobile search results, eliminating the profile photo and circle count.