I believe the "OWB" stands for "Outside the WaistBand", or open carry.
I do it all the time here in AZ, and I'm 24, frequently unshaven (razor blades are expensive, I shave every third day to save on blades), and stand to lose about 20 pounds. I look nothing like a cop, but nobody give me so much as a second look. I love AZ.
OWB = Outside the waistband = on the belt or in a paddle holster. It does not necessarily mean open/exposed carry. I always wear my gun in a belt holster (too much of me IWB already) but it is always concealed.