Physical distance also sends emotional messages. One anthropologist found that people feel a sense of ownership of the space that directly surrounds them (Hall, 1966) They attempt to protect their personal space by "keeping their distance" from other people, and they feel uncomfortable if someone moves into this space. People will attempt to restore the proper space, the size of which is largely a function of the type of interaction and attraction involved. People allow friends to come closer than strangers. Thus, one way in which we communicate attraction is to get physically close to others.