Color block dresses have been around since the 60's and Yves Saint Laurent was one of the first designers to use the color blocking pattern on a dress (one of his first dresses is on display in the Metropolitan Musuem of Art). 

A color block dress consists usually of the primary colors or complimentary colors, arranged in shapes on a dress surrounded by black lines or borders. 

I found the below dress recently and fell in love with the multiple colors and shapes on the dress. The fit, length of the dress and sleeves were perfect (besides if you find a dress with sleeves buy it, you don't find many of those any more).  And of course the $4.00 price tag made it the perfect dress for me!