A macro meme first appeared around 2010 as a part of the "rage comics" series of memes. Originally used to display wearyness/content mood. Wojak saw a huge revival around 2020 as a template for various macro memes and spawned several derivatives, either as a depiction of a stereotypical types of internet users or simply as a reaction images.
The name is taken from the Polish word "wojak", meaning "soldier" or "fighter".