WTF Is This Shit!? is an internet catchphrase, popularly used in various image macros where a character looks confused. It is used to signify disapproval of someone else's post, when they post something that is either really stupid, badly written, vulgar, or otherwise out of place.
The first instance of the catchphrase being used in an image macro is supposedly from December 10th, 2006, uploaded on Flickr. It used a picture of Annoyed Picard from Star Trek, making an exaggerated hand gesture, seeming to point out to something that he doesn't approve of. This specific hand gesture became one of the defining elements of "WTF is This Shit" image macros, although it isn't always present.
"WTF is This Shit" can also be considered as a more hostile variant of "What is This I don't Even".
Definition by Urban Dictionary
Urban Dictionary defines "WTF is This Shit" as follows:
A phrase uttered by a dumbfounded person or persons after witnessing an act committed by an individual that is so incredibly stupid, ridiculous, retarded, moronic, and asinine that no other words can describe the idiocy of this certain individual.
On January 23rd, 2012, a Quickmeme page for "Annoyed Picard" was created, which featured a screen capture of Picard with an outstretched arm accompanied by captions expressing incredulous frustration.
On June 23rd, a new Quickmeme page was created titled "Annoyed Picard HD", which featured a higher resolution version of the original Annoyed Picard screen capture. As of July 24th, 2012, the "Annoyed Picard" Quickmeme page has accumulated over 5,500 submissions and the "Annoyed Picard HD" page has received over 2,800 submissions. The same image has been used in the series of image macros using the caption "WTF is This Shit?".