What is meme?

Term for an idea considered as a replicator, especially with
the connotation that memes parasitise people into propagating
them much as viruses do.

Memes can be considered the unit of cultural evolution. Ideas
can evolve in a way analogous to biological evolution. Some
ideas survive better than others; ideas can mutate through,
for example, misunderstandings; and two ideas can recombine to
produce a new idea involving elements of each parent idea.

The term is used especially in the phrase "meme complex"
denoting a group of mutually supporting memes that form an
organised belief system, such as a religion. However, "meme"
is often misused to mean "meme complex".

Use of the term connotes acceptance of the idea that in humans
(and presumably other tool- and language-using sophonts)
cultural evolution by selection of adaptive ideas has become
more important than biological evolution by selection of
hereditary traits. Hackers find this idea congenial for
tolerably obvious reasons.