A plot style is an object property, similar to linetype and color. A plot style can be assigned to an object or a layer. A plot style controls an object's plotted properties, including
Using plot styles gives you great flexibility because you can set them to override other object properties or turn off the override as needed.
Groups of plot styles are saved in either of two types of plot style tables: color-dependent (CTB) or named (STB). Color-dependent plot style tables set style based on the color of the object. Named plot styles can be assigned to an object independent of color.