Something that people claim to do when they supposedly want to speak their mind. Used often on the Internet by people who are about as quiet as a church mouse in real life.
Now, on the other hand, there are people who thinking that keeping it real is synonymous with being an asshole or bitch. They say that most people cant handle such realness, and usually get offended when you keep it real by calling them such. All in all, most people just dont wanna deal with such childishness, contrary to what they tell you.