1. A method of categorizing color palettes comprising: associating natural language terms with achromatic entity categories of a set of achromatic entity categories; mining a collection of color palettes which have been previously labeled with comments of reviewers to form a dataset of labeled color palettes; assigning entity categories from the set of achromatic entity categories to a subset of the labeled color palettes in the dataset of color palettes based on matching natural language terms in the labels of the color palettes with the natural language terms associated with the achromatic entity categories, each color palette in the subset consisting of a sequence of from two to one hundred swatches, each swatch in the color palette being of a different color, each color palette in the dataset of color palettes differing from each of the other color palettes in the dataset with respect to at least one of its swatches; extracting color-related features from each of the color palettes; and with a computer processor and based on the assigned entity categories and color related features of the labeled color palettes, training a classifier to categorize a color palette into at least one of the set of achromatic entity categories based on its extracted color-related features.