William Caxton was an English merchant, diplomat, writer, and printer. He is known for introducing the printing press to England and for being the first English retailer of printed books. Caxton played a significant role in the development of English literature by printing and publishing works such as Chaucer's "Canterbury Tales" and Malory's "Le Morte d'Arthur." His efforts helped to standardize the English language and make literature more accessible to a wider audience.