Great Question! So, a lot of people think it means they will "quack like a duck". Silly and funny behaviors seen on stages are from Stage Hypnosis, most often meant for entertainment. Hypnosis or clinical hypnosis, is a trance like state (there are multiple levels of trance), that when offered suggestions in this state, bypass the conscious mind (critical thinker and gatekeeper) and allow those suggestions to go straight to the unconscious mind. This is used to create positive change in a person's life.
Basically, we create suggestions you wish for yourself TOGETHER, and relax/suspend the mind and body to most easily receive and use those messages for positives outcomes.
So what does THAT mean. The unconscious mind is in a way, the inner mind or background mind. It is always going, always thinking, and is always what is controlling all of your 'automatic systems', like breathing, heart beat, and other functions you don't have to "think" about, in order for them to happen...thankfully! It is also where dreams come from and what is activated during REM sleep. It stores the patterns, good and bad processes, traumas, memory bits, and more! The unconscious mind is very unique in how it seems to process, bring up information, often speaks in metaphor, images, and has some interesting scare tactics! To understand this a little bit, just think about the many different types of dreams you have had (if you remember), maybe some of the patterns in your life -- both good and bad, and why it is you are the way that you are (whatever that entails). It's pretty amazing!!