.

components/sections/preface/index.js

@@ -52,7 +52,7 @@ var Preface = React.createClass({
         <p>—Pomax (or in the tweetworld, <a href="https://twitter.com/TheRealPomax">@TheRealPomax</a>)</p>
 
         <div className="note">
-          <h2>Note: All Bézier graphics are interactive.</h2>
+          <h2>Note: virtuall all Bézier graphics are interactive.</h2>
 
           <p>This page uses interactive examples, relying heavily on <a href="http://pomax.github.io/bezierjs/">Bezier.js</a>,
           as well as "real" maths (in LaTeX form) which is typeset using the most excellent <a href="http://MathJax.org">MathJax</a> library.
@@ -61,6 +61,16 @@ var Preface = React.createClass({
           add them back in, but it didn't feel like it should hold up deploying this update compared
           to the previous years' version.</p>
 
+          <h2>This book is open source.</h2>
+
+          <p>This book is an open source software project, and lives on two github repositorites. The
+          first is <a href="https://github.com/pomax/bezierinfo">https://github.com/pomax/bezierinfo</a> and
+          is the purely-for-presentation version you are viewing right now. The other repository is
+          <a href="https://github.com/pomax/BezierInfo-2">https://github.com/pomax/BezierInfo-2</a>, which
+          is the development version, housing all the html, javascript, and css. You can fork either
+          of these, and pretty much do with them as you please, except for passing it off as your
+          own work wholesale, of course =)</p>
+
           <h2>How complicated is the maths going to be?</h2>
 
           <p>Most of the mathematics in this Primer are early high school maths. If you understand basic