Someone who knows that the SHTF is enevitable although it is unknown when this is going to take place. Realists can often be identified by their gear, it's usually simple yet effective. Examples of realist gear are MRE's, practical firearms, tents, lanterns, Etc.
Liberal Dumbass: Gee Mr. Realist why do you need guns? The government can take care of you. Plus guns are dangerous and only crazies have guns.
Rupert the Realist: Because it's impractical to keep a cop in my pocket and people like you drive me crazy. Now get off my porch before you learn the reality... OF CASTLE DOCTRINE!