Google+ (also known as GooglePlus and G+) is Google’s major social networking platform, created June 28, 2011. There are apparently approximately 100 million active monthly users of Google+ (as of September 2012). The most unique thing about Google+ is that it exists across multiple Google properties, unlike Facebook or Twitter, which only can be accessed through Facebook.com or Twitter.com. Google+ can be accessed through many of Google’s websites.
When it first came out, many people assumed that Google+ represented a threat to Facebook. However, Google+ is an asynchronous social network, which means that, unlike Facebook, you don’t need both individuals to consent before establishing a relationship together. (On Facebook, “friend requests” are made, and they must be accepted before two individuals establish a connection.) On Google+, on the other hand, you can “follow” someone without their consent. This qualifies Google+ as an asynchronous social network, which means it is more of a competitor to Twitter.
Google+ is Google’s fourth major attempt at creating a thriving social network: first came Orkut (2004), then came Google Friend Connect (2008), and most recently Google Buzz (2010).
To make things somewhat confusing, Google also replaced its Google Places (business listings) with an annoyingly named “Google+ Local” product, which is essentially Google+ for local businesses.