When I was first instructed in hunting by my Dad, I was told to load my rifle's magazine, rack a round into the chamber and put the safety on. You never take the safety off until you are about to take a shot.
On the TV hunting programs, I have noticed out west and in some other countries, that they carry their rifles with an empty chamber and do not put a round in until just before they are ready to take a shot at an animal. Where I hunt, if you did that, you would spook the game most of the time because they are relatively close when you see them.
Is that a common practice among a lot of hunters, or it that a TV show thing?