Can I be hypnotised without my knowledge?

If you've ever watched TV or listened to radio, then you have been hypnotized.  It just doesn't have to happen with a pocket watch and someone speaking in a deliberately hypnotic voice.  Almost anyone that watches television gets hypnotised without realising it. The level of concentration and focus on the screen images and what is being said, at a point when we are totally relaxed, almost to trance-like conditions, creates the right environment for suggestions to be planted and take root in our subconsciousness. We then find ourselves craving certain foods, or warming to a politician or actor in a certain way after wards.