Public relations, often abbreviated to PR, deals with how a company is seen by the media and the general public. A company's image changes depending on what information is disclosed, so controlling the spread of information is essential to maintaining a good reputation.
PR is different from advertising because companies don't pay media outlets or newspapers to promote them. Through the careful disclosure of information, a company can control its public image very precisely. Large companies typically have entire PR departments, where many people work together, employing various tactics to make sure the firm maintains a good reputation in the public eye.