Understanding Comics by Scott McCloud

From the blurb:

Praised throughout the cartoon industry by such luminaries as Art Spiegelman, Matt Groening, and Will Eisner, this innovative comic book provides a detailed look at the history, meaning, and art of comics and cartooning.

Bio: Scott McCloud has been writing and drawing comics professionally since 1984. His first series, Zot!, garnered multiple nominations in the prestigious Harvey and Eisner awards. His book Understanding Comics was a New York Times Notable book for 1994, and has since been translated into over 16 languages.