A style is a tool stack that was originally created for one photo that can be applied to other photos. Using styles is the same as copying & pasting tool stacks except that a style is saved with a name for use at any later time.
LightZone comes bundled with many ready-made styles that you can use and learn from. Additionally, you can create your own styles. Lastly, you can replace the default tone curve for a camera with a style you create.
To learn more about working with styles, click a link below.