If You Know What I Mean pairs a vectorized still of Rowan Atkinson as Mr. Bean, eyebrows raised and mouth slightly pursed, with the caption "if you know what I mean"1. The face is dropped at the end of a post or image macro to signal a sexual double entendre the reader is supposed to catch, a trick TV Tropes files under the "Lampshaded Double Entendre" trope2.

Though it started as a rage face, the character is often used the same way as reactions like You Don't Say? or We've Got a Badass Over Here, sitting in the final panel of a vertical rage comic to punctuate the joke1. The phrase itself is much older than the image, with Urban Dictionary entries defining it as a "way to make a statement 'dirty'" going back to 20033.

The convention is simple: end a sentence with an unambiguously innocent phrase that also reads as an innuendo, then paste the Mr. Bean face directly under the text or in the final panel of a vertical rage comic. It typically works best when the double meaning is thin enough that most readers would catch it anyway, since the face is doing the "lampshading" work of pointing at the joke2. The phrase alone, without the image, is often used the same way in plain text conversations, a habit Urban Dictionary already documented years before the rage face existed3.