http://www.expression-web-tutorial.com/Types_CSS_Styles.html#.U0wGMFWSxf8

http://www.expression-web-tutorial.com/Types_CSS_Styles.html#.U0wGMFWSxf8

There are three kind of css styling we are using, 1.Internal(Embedded) : Inner styles are placed within the area website. 2.Inline : Inline styles are placed within tag.Can not use later on. 3.External : External style is a separate page which connected to particular web page. We can use it many periods.Joomla Designer