Q: What is copypasta
A: Copypasta is, as its name suggests, text which is basically cut and pasted. (The name comes from the act of 'cutting and pasting' on a computer, but it is a generic name for plagiarism, and generally any form of copying other people's writing. Take copying an article out of a magazine, and typing it in yourself, for example. No Ctrl X, Ctrl V there, but that's still Cut and Paste.) Now any person who has ever done any serious programming will tell you, if you need to cut and paste, you're probably doing something wrong. If the information is present in one place, that's enough. Instead of cutting and pasting, a link will usually suffice.
Q: Did you just cut and paste Cut and paste writeups will die?
A: Well, not exactly. I took the part that explains what it is, and changed a few words around.
Q: Did you ACTUALLY READ the node and understand that what you did is wrong?
A: See what I did there? That's actually the second half of the explanation.
Copypasta is 1. usally slightly altered to appear to be original content 2. posted with the intent to troll or spam 3. would be compelling or interesting had it not posted several hundred times before.