Katchor embodies his love of the fading small-business community of New York City in the title character, a downtrodden schlep who wanders the streets taking pictures and being sidetracked into surreal escapades. Strips often depict Knipl's chance encounters with obscure, marginal businesses (e.g. a company that distributes newspaper weights to newsstands), eccentric hobbyists, and enigmatic details of the urban landscape. There is rarely continuity between the strips, and Knipl is the only recurring character.
A collection of Julius Knipl strips was published in 1991 by Penguin Books (as a RAW One-Shot) as Cheap Novelties: The Pleasures of Urban Decay. Another collection was published in 1996 by Little, Brown and Company under the title Julius Knipl, Real Estate Photographer: Stories. Pantheon Books published a third volume of strips, The Beauty Supply District, in 2000. Each book includes one long story in addition to the self-contained weekly strips. Translated collections of the strip in French and Japanese have also been released.
The word knipl means roughly "nest egg" in Yiddish.