A meme is a piece of information that is passed from one entity (person, book, etc.) to another. Often memes are social or cultural in nature and are ways aspects of culture are passed from person to person so that the information is understood. They can also be ideas, parts of ideas, sounds, songs, and all sorts of other pieces of information that get passed on. Memes have been compared to viruses because of the way they self perpetuate and spread from person to person.