Introduction

Euclid's *Elements* form one of the most beautiful and influential works of science in the
history of humankind. Its beauty lies in its logical development of geometry and other branches of
mathematics. It has influenced all branches of science but none so much as mathematics and the exact
sciences. The *Elements* have been studied 24 centuries in many languages starting, of course,
in the original Greek, then in Arabic, Latin, and many modern languages.

I'm creating this version of Euclid's *Elements* for a couple of reasons. The main one is to
rekindle an interest in the *Elements,* and the web is a great way to do that. Another reason
is to show how Java applets can be used to illustrate geometry. That also helps to bring the
*Elements* alive.

The text of all 13 Books is complete, and all of the figures are illustrated using the Geometry Applet, even those in the last three books on solid geometry that are three-dimensional. I still have a lot to write in the guide sections and that will keep me busy for quite a while.

This edition of Euclid's *Elements* uses a Java applet called the Geometry Applet to
illustrate the diagrams. If you enable Java on your browser, then you'll be able to dynamically
change the diagrams. In order to see how, please read Using the Geometry
Applet before moving on to the Table of Contents.