Dream a Little Meme

From Wikipedia:

The term meme ([miːm] in the IPA; rhymes with "dream"; from the Greek word mimema for 'something imitated') first came into popular use with the publication of the book The Selfish Gene by Richard Dawkins in 1976. Though Dawkins defined the meme as "a unit of cultural transmission, or a unit of imitation," memeticists vary in their definitions of meme. The lack of a consistent, rigorous and precise definition of a meme remains one of the principal criticisms leveled at memetics, the study of memes.

The notion of a unit of social evolution, and a similar term (from Greek mneme, 'memory'), first appeared in 1904 in a work by the German evolutionary biologist Richard Semon: Die Mnemische Empfindungen in ihren Beziehungen zu den Originalenempfindungen, translated into English in 1921 as The Mneme.

Different definitions of meme generally agree, very roughly, that a meme consists of some sort of a self-propagating unit of cultural evolution having a resemblance to the gene (the unit of genetics). Dawkins introduced the term after writing that evolution depended not on the particular chemical basis of genetics, but only on the existence of a self-replicating unit of transmission — in the case of biological evolution, the gene. For Dawkins, the meme exemplifies another self-replicating unit, and most importantly, one which he thought would prove useful in explaining human behavior and cultural evolution.

In casual use, the term meme often refers to any piece of information passed from one mind to another. In this sense, it is closely related to folklore (as it is studied in the academy), in that folkloristics deals with the informal communication of cultural information. This usage more closely resembles the analogy of "language as a virus" than Dawkins' analogy of memes as replicating units. This definition has come into popular use on the Internet to refer to phenomena such as Obey Giant, "All your base are belong to us", Blogebrity and Icy Hot Stuntaz.