The Swatches panel (Window > Color > Swatches) lets you create and name colors, gradients, or tints, and quickly apply them to your document. Swatches are similar to paragraph and character styles; any change you make to a swatch affects all objects to which the swatch is applied. Swatches make it easier to modify color schemes without having to locate and adjust each individual object.
When the fill or stroke of selected text or an object contains a color or gradient applied from the Swatches panel, the applied swatch is highlighted in the Swatches panel. Swatches you create are associated only with the current document. Each document can have a different set of swatches stored in its Swatches panel.