De Worde is generally credited for moving English printing away from its late-medieval beginnings and toward a "modern" model of functioning. Caxton had depended on noble patrons to sustain his enterprise; while de Worde enjoyed the support of patrons too (principally Margaret Beaufort, mother of King Henry VII), he shifted his emphasis to the creation of relatively inexpensive books for a commercial audience and the beginnings of a mass market. Where Caxton had used paper imported from the Low Countries, de Worde exploited the product of John Tate, the first English papermaker. De Worde published more than 400 books in over 800 editions (though some are extant only in single copies and many others are extremely rare). His greatest success, in terms of volume, was the Latin grammar of Robert Whittington, which he issued in 155 editions. Religious works dominated his output, in keeping with the tenor of the time; but de Worde also printed volumes ranging from romantic novels to poetry (he published the work of John Skelton and Stephen Hawes), and from children's books to volumes on household practice and animal husbandry. He innovated in the use of illustrations: while only about 20 of Caxton's editions contained woodcuts, 500 of Wynkyn de Worde's editions were illustrated.