Comic strips began appearing in American newspapers in the late 19th century, with The Yellow Kid—a bald, snaggle-toothed boy who hung out in a grungy alley with several other odd-looking characters—generally recognized as one of the first.
The Katzenjammer Kids, which began appearing in 1897, drawn by German immigrant Rudolph Dirks, was the first strip to feature “sawing logs” to indicate a sleeping character’s snoring, “swirling stars” to illustrate pain, and word balloons for dialogue.
In the 1930s, newspaper comics moved beyond their original humorous subjects and began to include adventures and exploits of Popeye, Tarzan, Buck Rogers and other action-oriented characters. “Soap opera” themes were introduced in the 1940s with Mary Worth and Judge Parker.
The long-running Gasoline Alley, which began in 1918 and continues to this day, was the first strip to feature characters that aged through the generations, as opposed to other comics, in which characters never looked any older year after year.