It is ingrained in our nature to want to relieve stress, pass time, or even utter dissatisfaction through humor. This master’s thesis tells the story of humor from its very beginnings, gives an overview of the most important findings in the field of humor, and presents the main three recent theories of humor – Theory of Incongruity, Theory of Superiority, and Theory of Release. Moreover, after dealing with humor as such, this thesis focuses on the linguistic means of achieving humorous effect in Kurt Vonnegut’s satirical novel Galápagos. Even though irony, sarcasm, and satire can be seen as separate categories of humor, as will be shown in this thesis, I believe that Kurt Vonnegut is a prime example of why it is better to view them as a whole when it comes to utilizing humor in literature to achieve a greater purpose than merely causing others to laugh. In the final part of the thesis practical examples taken from Vonnegut’s novel are provided and fitted into the category of irony and/or sarcasm referred to in the theoretical part of the thesis. In principle, there are two main aims of this thesis. The first one is to show from a linguistic perspective that humor in literature can be an effective means of achieving much more than just a humorous effect. The second aim of the thesis is, on the one hand, to demonstrate that Vonnegut’s humor is largely based on mechanisms of irony, which Vonnegut uses to critique human intelligence and make fun of human pretensions and the randomness of life, and also that Galápagos a prime example of a satirical novel on the other hand.