The term meme was coined in 1976 by British evolutionary biologist Richard Dawkins in his work The Selfish Gene. Dawkins conceived of memes as the cultural parallel to biological genes and considered them, in a manner similar to "selfish" genes, as being in control of their own reproduction, thus serving their own ends. 

So in those terms, memes carry information, are replicated, and are transmitted from one person to another, and have the ability to evolve. Memes mutate at random, undergoing natural selection, and can take a variety of forms, such as an idea, a skill, a behaviour, a phrase, or a particular fashion.

The replication and transmission of a meme occurs when one person copies cultural information from another person. It is carried out primarily by means of verbal, visual, or electronic communication, ranging from books and conversation to television, e-mail, or the Internet. Naturally, those memes that are most successful in being copied and transmitted become the most prevalent within a culture.

The exploration of relationships between cultural evolution, cultural transmission, and imitation has led to interesting theories about memes. For example, various ideas have emerged about the nature of memes, wondering if they are beneficial, neutral, or harmful.

For example, some scholars say memes may be interpreted as being inherently harmful because they are parasites or viruses of the mind; once assimilated into the human mind, their chief purpose becomes their own replication, with humans having little or no control over them.

Some memes, on the other hand, are benign or beneficial but can become dangerous because after they have been seeded in the human mind, they lend themselves to being misused or abused. Consider memes associated with religious or political ideas, for example. They may benefit the people who carry them, but those same memes, when imposed on people whose religious or political memes are different, may cause harm, such as through the loss of religious traditions or social or political stability.