While the true origin of the O RLY? catchphrase is unknown, it is likely that it was simply a shortened version of "oh really" which was commonly used throughout the internet and spread through chat rooms and bulletin boards. The phrase has over time become more of an inside joke as people usually use "o rly" as a way to express disbelief of something which seems silly or absurd.

Unlike the catchphrase, the origin of the O RLY owl is known. The O RLY owl was first created on an imageboard, 4chan, when the word "repost" was filtered to "owl". Owl quickly became widespread, spawning many new image macros involving owls typically to display certain emotions such as laughter, enjoyment, anger, or disapproval. After the creation of the O RLY owl it was reposted and modified frequently, usually in response to various subjects, and usually for comedic value. The O RLY owl eventually spread to other web sites such as YTMND, spawning even more variation.