What is a teacher?

As far as I am concerned, I don't expect a teacher to be as attractive as a walking Wikipedia. I wish a teacher should be a person who can understand the mind and level of a student,so that he can teleport themselves virtually. To improve the style of thinking they could guide through different paths they have seen or they wish to see. A class must be like an adventure trip,not a drill exercise. A teacher must be always a thinker,who can spread optimism and hope as they smiles. After all teaching is more a responsibility than a job.
Luckily In my case,i had more teachers who have never taught me in class but been the perfect ones to guide me.