Styles panel
Styles are layer effect presets which can be applied to image layers, type layers or vector layers. New custom layer effect combinations can be saved as Styles, where they are represented in the panel by an icon, which will visually indicate the outcome of applying the style to a square button shape. Styles can incorporate Pattern and Gradient fill layer effects.
To find out more about working with and saving styles, refer to the Layers Styles section of the help guide.