Written and illustrated by American book writer and cartoonist William Steig, it is about a repugnant, green ogre who leaves home to see the world and ends up marrying an ugly princess.

[6] His books became known for "graphically repeated themes of stark separation and warm reunion" between parents and their children while maintaining the "wit" that was characteristic of his cartoons.

[7] Steig's artwork in his children's books was noted for "rich" use of colors[8] and were made using watercolor painting and ink.

Shrek is a repugnant, green-skinned, fire-breathing, seemingly indestructible monster who enjoys causing misery with his repulsiveness.

Shrek soon encounters a witch, who, in exchange for his rare lice, reads his fortune: by uttering the magic words "Apple Strudel", he will be taken by a donkey to a castle, where he will battle a knight and marry a princess who is even uglier than him.

Inside the castle, Shrek is terrified when he appears to be surrounded by an army of similarly hideous creatures, but regains his resolve and self-esteem upon discovering that he is in the hall of mirrors.

He finally meets the princess; mutually smitten by their shared ugliness, they marry and live "horribly ever after, scaring the socks off all who fell afoul of them".

[13] A reviewer for The New York Times highlighted the illustrations and Steig's "perfect-pitch ear for daffy English idiom".

[14] Michael Dirda for The Washington Post considered the writing and pictures to be "relatively simple", but "such an ingratiating, cheery book that no one will be able to resist it".

[20] Professor Victoria Ford Smith in 2017 considered Steig's artwork "childlike", comparing it to the work of Quentin Blake.

"[22] In 2019, Rumaan Alam in The New Yorker highlighted the book as a story where "the bad guy gets a happy ending" and noted that "sometimes life works that way.

According to the professor Lewis Roberts, Shrek experiences several "moments of crisis" in the book, first when he has a nightmare about children and later when he enters the hall of mirrors.

Roberts concludes by saying that "The book rehearses the crises of subjectivity all children must face, and then reassures and amuses its readers by showing how even a hideous figure such as Shrek can find resolution.

[28][29][30] Shrek was released on May 18, 2001 in CGI, starring the voices of Mike Myers, Eddie Murphy, Cameron Diaz, and John Lithgow.

[4] Several critics highlighted differences between the Shrek film and Steig's original version, including the addition of characters and changing the plot and morals.