What does TSA Pre check mean? My boarding pass has it on and I was diverted through a less security than other passengers.?

It means you have been pre-screened and determined to be a low risk passenger. You can go through the line with less security - you don't have to take off shoes or belts, can leave your computer in it's bag and can leave your liquids in the zip lock bag inside your carry on. Sometimes frequent flyers get this when flying. You can also sign up for TSA-Pre and pay $80 to get TSA Pre all the time.

Somehow, they know about you and believe you are not a risk. I have had this happen to me on about 5 occasions. I never asked for special treatment.