Cascading Style Sheets
Cascading Style Sheets (CSS) are a collection of formatting rules which
control the appearance of content in a web page. With CSS styles you have
great flexibility and control of the exact page appearance, from precise
positioning of layout to specific fonts and styles.
CSS styles let you control many properties that cannot be controlled
using HTML alone. For example, you can assign custom list bullets and
specify different font sizes and units (pixels, points, and so on). By
using CSS styles and setting font sizes in pixels, you can ensure a more
consistent treatment of your page layout and appearance in multiple
browsers. In addition to text formatting, you can control the format and
positioning of a block-level elements in a web page. For example, you can
set margins, borders, float text around other text, and so on.