The most popular comic strip with a recurring theme of math is xkcd. It is the only one regularly published and presented in a standard comic format. Other math related comic strip collections include Comic Math and Spiked Math Comics. Many comics have individual strips with math jokes, but are not dedicated to math as a topic.
xkcd is a webcomic created by Randall Munroe. The creator of the comic describes it as a simple stick figure cartoon strip that discusses topics relating to technology, science, mathematics and relationships. The subject matter of the comic includes statements on life and love, but a dominant number of the strips contain mathematics or computer science jokes. These jokes usually refer to university-level subjects, but most are written in such a way that a clear understanding of the subject is not required to get the joke. Some strips also feature simple humor or pop-culture references. Although it has a cast of stick figures, the comic often features landscapes, intricate mathematical patterns, such as fractals, and elaborate graphs and charts.
Since July 2012, there has been a branch of xkcd called "xkcd What-If," updated every Tuesday. "What If?" answers unusual reader-submitted science questions in a humorous, but always mathematically sound way. It is presented in the format of an article rather than a traditional comic strip.