An abbreviation of the phrase “why you no,” Y U NO is an image of a stick-figure wearing a distinct facial expression of irritation and anger. It is superimposed with text to form an image macro series that uses a shorthand style commonly used in text messaging as well as erroneous grammar in order to address/question a certain topic. The meme is also sometimes known as TXT BAK or Y U NO guy on the Internet.
The clearly disturbed face of the guy is considered to be based from a character from Gantz, a Japanese sci-fi manga / anime series in which two friends died and somehow transported themselves to an unreal world full of violence. The expression is particularly found in Chapter 55: Naked King, which was first published in February 2002 and then translated into English in June 2009.
Before it was exploited as the Y U NO image macro, the image has spread around 4chan imageboards.
The first appearance that came with the Y U NO text was seen in a LOLTumblrWallpapers post that garnered a combination of more than 10,000 reblogs & likes on the social blog Tumblr. It said, “I TXT U, Y U NO TXT BAK!?”
As it started to become popular, several websites that allow users to generate their own meme uploaded the image as an exploitable or a blank template. The common pattern in the text would be “[subject], Y U NO [verb]?”.
Best of Y U NO