People can communicate how they feel about someone by the way they touch them. For example, someone may hold hands with a romantic partner or pat a friend on the back when they want to express support or approval.
Touch can be a ritualistic quality to indicate when people are beginning or ending an interaction with someone. For example, when someone walks into a job interview, it is common to shake hands with the interviewer; when someone see their neighbor, they often wave to say hello, and when someone leaves a friend’s house at the end of a visit, they may give the friend a hug.
Sometimes a touch is not used in order to express feelings or thoughts, but rather to accomplish something. Examples of this would be opening a door for someone or touching someone’s head to determine if they have a fever.
Sometimes people communicate something to others by avoiding touching them, such as when they are angry with someone. Also, when people want to show that they are not interested in someone romantically, they may rebuke their touches.