What is a rick roll?

A rickroll is an internet prank that involves tricking someone into clicking a hyperlink that leads to the music video for the Rick Astley song "Never Gonna Give You Up." The prank became popular in the mid-2000s and has since become an internet phenomenon. The term "rickrolled" has even been added to the Oxford English Dictionary. The prank is often used as a way to add humor to a comment thread or to trick someone into clicking a link without warning. While some people find the prank amusing, others find it irritating or annoying.