A comic strip is a sequence of cartoons, arranged in interrelated panels to display brief humor or form a narrative, often serialized, with text in balloons and captions. Traditionally, throughout the 20th and into the 21st century, these have been published in newspapers and magazines, with daily horizontal strips printed in black-and-white in newspapers, while Sunday papers offered longer sequences in special color comics sections. With the advent of the internet, online comic strips began to appear as webcomics.

Strips are written and drawn by a comics artist, known as a cartoonist. As the word "comic" implies, strips are frequently humorous. Examples of these gag-a-day strips are Blondie, Bringing Up Father, Marmaduke, and Pearls Before Swine. In the late 1920s, comic strips expanded from their mirthful origins to feature adventure stories, as seen in Popeye, Captain Easy, Buck Rogers, Tarzan, and Terry and the Pirates. In the 1940s, soap-opera-continuity strips such as Judge Parker and Mary Worth gained popularity. Because "comic" strips are not always funny, cartoonist Will Eisner has suggested that sequential art would be a better genre-neutral name.

Every day in American newspapers, for most of the 20th century, there were at least 200 different comic strips and cartoon panels, which makes 73,000 per year. Comic strips have appeared inside American magazines such as Liberty and Boys' Life, but also on the front covers, such as the Flossy Frills series on The American Weekly Sunday newspaper supplement. In the UK and the rest of Europe, comic strips are also serialized in comic book magazines, with a strip's story sometimes continuing over three pages.