What Does Google Plus (Google+) Mean?

Google Plus (Google+ or just G+) is a social network built over Web 2.0 standards and specification owned and operated by Google Inc.

Techopedia Explains Google Plus (Google+)

Google Plus social network provides the services and capabilities of a typical social network along with some unique features related to Google search. Most notable is users’ ability to +1 content, which can boost a page’s rank, at least for those who are connected to the person who promoted it.