Copypasta

A copypasta is a block of text which is copied and pasted across the Internet by individuals through online forums and social networking websites. Copypastas are said to be similar to spam.
History.
The word "copypasta" was first used on Usenet groups in 2006.
Etymology.
The term "copypasta" is derived from the computer term "copy/paste", and can be traced back to an anonymous 4chan imageboard from 2006.
Notable examples.
Navy Seal.
The Navy Seal copypasta is a lengthy, comically written, aggressive attack paragraph against a "kiddo", written in the voice of the stereotypical "tough guy", listing absurd accomplishments such as having "over 300 confirmed kills" and being "trained in gorilla warfare". This copypasta is often reposted as a humorous overreaction to an insult and is thought to have originated in a post on a 4chan message board from 11 November 2010.
"Bee Movie".
The "Bee Movie" copypasta dates back to 2013 where users would post the entire script of the "Bee Movie" onto websites such as Reddit and Tumblr. This was popularised around the time when edits of the film were first being posted and popularized on YouTube in late 2016.
Technology.
Copypasta can refer to a piece of code that was copy/pasted. Discussions of copypasta can be found in the code history of Linux, e.g.: "This very much looks like copypasta" (this looks like copy/pasted code and was not originally authored) and "Copypasta mistake" (this code was copy/pasted and not correctly amended).