A lolcat, or LOLcat, is an image macro of one or more cats. Lolcat images' idiosyncratic and intentionally grammatically incorrect text is known as lolspeak.

An image macro is a piece of digital media featuring a picture, or artwork, with some form of text superimposed. The text frequently appears at the top and bottom of the image. Image macros were one of the most common forms of internet memes in the 2000s, and often featured witty messages or catchphrases, although not all image macros are necessarily humorous. LOLcats, which are images of expressive cats coupled with texts, are considered to be the first notable occurrence of image macros. Advice animal image macros, also referred to as stock-character macros, are also highly associated with the image macro template.