'Shrek!' is a picture book written and illustrated in 1990 by American cartoonist William Steig about a repugnant and monstrous green ogre who leaves home to see the world and ends up saving a princess.

Steven Spielberg acquired the rights for the book in 1991, planning to produce a traditionally animated film based on the book. However, around the time DreamWorks was founded, producer John H. Williams brought the book to DreamWorks, and co founder Jeffrey Katzenberg was interested in the concept. As a result, DreamWorks ended up acquiring the rights for the book in 1995, and Katzenberg quickly put the film in active development.

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