First HTML Document

This document has been structured, styled, and given behavior in three seperate files:

First.html provides structure and content.
First.css defines presentation format through a series of cascading styles.
First.js defines javascript event handlers responsible for changing presentation properties on list items on mouseover and mouseout, and showing an alert when the first heading is clicked.

This example demonstrates using HTML to establish document structure and content, using CSS to set presentation format for the document, and Javascript to define behaviors in response to user events.

Note that the example also demonstrates separation of these responsibilities into their own modules. This establishes two important characteristics for this document:

Changes to style or behavior need to be made in only one place, even if many documents use these styles and behaviors.
On the first document load, the style file, First.css, and Script file, First.js, will be loaded. On subsequent loads of any document that uses these files, they will be drawn from the browser's cache, rather than loaded from the server, decreasomg page load times and server CPU load.