Facebook introduced clickable hashtags to the site. Instagram, Twitter, Tumblr and Google+ all already have hashtags, which function as tags people can click to see all posts that include a specific term.

But Facebook has added hashtags to connect people with others they know and toward uniting users with the public at large. Ultimately, Facebook's latest feature risks not only watering down its value proposition and introducing an identity crisis, but also highlighting for its users just how messy the site has become. Facebook has struggled lately with spammers, fake accounts and offensive sub-communities.