A teacher is a person who helps people to learn. A teacher often works in a classroom. There are many different kinds of teachers. Some teachers teach young children in kindergarten or primary schools. Others teach older children in middle, junior high and high schools. Some teachers teach adults in more advanced schools (for example, colleges and universities). Some are called professors.
There are different ways of teaching. Most teachers use a variety of methods to teach. Teachers often explain new knowledge, write on a blackboard or whiteboard, sit behind their desks on chairs, help students with their work, or mark students' work. They may use a computer to write tests, assignments or report cards for the class.