Rather than go on and on about his life, I'm going to link to some excellent articles here and here and just show you a few of my personal favorites of his wonderful illustrations.
“But the wild things cried,
'Oh please don’t go – we’ll eat you up – we love you so!'
And Max said, 'No!'
The wild things roared their terrible roars and gnashed their terrible teeth
and rolled their terrible eyes and showed their terrible claws,
but Max stepped into his private boat and waved goodbye.”
– Maurice Sendak
June 10, 1928 - May 8, 2012
From "Where the Wild Things Are"
From "A Kiss For Little Bear", written by Else Holmelund Minarik.
From "Chicken Soup With Rice"
There are more books illustrated by Sendak that I love that I can't find images for just now. They include:
"And I Mean It, Stanley!" by Crosby Newell Bonsall
Other "Little Bear" books, by Else Holmelund Minarik