diff --git a/user_guide/changelog.html b/user_guide/changelog.html
index 20cb9b7..4f8c86f 100644
--- a/user_guide/changelog.html
+++ b/user_guide/changelog.html
@@ -62,6 +62,13 @@
 Hg Tag: </p>
 
 <ul>
+	<li>General changes
+		<ul>
+			<li>PHP 4 support is deprecated.  Features new to 2.0.0 may not be support PHP 4, and all legacy features will no longer support PHP 4 as of 2.1.0.</li>
+			<li>Scaffolding, having been deprecated for a number of versions, has been removed.</li>
+			<li>Plugins have been removed, in favor of Helpers.  The CAPTCHA plugin has been converted to a Helper and <a href="./helpers/captcha_helper.html">documented</a>.  The JavaScript calendar plugin was removed due to the ready availability of great JavaScript calendars, particularly with jQuery.</li>
+			<li>In-development code is now hosted at <a href="http://bitbucket.org/ellislab/codeigniter/">BitBucket</a>.</li>
+		</ul>
 	<li>Libraries
 		<ul>
 			<li>Added "is_object" into the list of unit tests capable of being run.</li>
@@ -94,7 +101,6 @@
 	</li>
 	<li>Other Changes
 		<ul>
-			<li>In-development code is now hosted at <a href="http://bitbucket.org/ellislab/codeigniter/">BitBucket</a></li>
 			<li>Increased randomness with <kbd>is_really_writable()</kbd> to avoid file collisions when hundreds or thousands of requests occur at once.</li>
 			<li>Switched some DIR_WRITE_MODE constant uses to FILE_WRITE_MODE where files and not directories are being operated on.</li>
 			<li><kbd>get_mime_by_extension()</kbd> is now case insensitive.</li>
diff --git a/user_guide/general/autoloader.html b/user_guide/general/autoloader.html
index 8d7f5d8..d697c8a 100644
--- a/user_guide/general/autoloader.html
+++ b/user_guide/general/autoloader.html
@@ -57,7 +57,7 @@
 
 <h1>Auto-loading Resources</h1>
 
-<p>CodeIgniter comes with an "Auto-load" feature that permits libraries, helpers, and plugins to be initialized
+<p>CodeIgniter comes with an "Auto-load" feature that permits libraries, helpers, and models to be initialized
 automatically every time the system runs. If you need certain resources globally throughout your application you should
 consider auto-loading them for convenience.</p>
 
@@ -66,7 +66,6 @@
 <ul>
 <li>Core classes found in the "libraries" folder</li>
 <li>Helper files found in the "helpers" folder</li>
-<li>Plugins found in the "plugins" folder</li>
 <li>Custom config files found in the "config" folder</li>
 <li>Language files found in the "system/language" folder </li>
 <li>Models found in the &quot;models&quot; folder</li>
diff --git a/user_guide/general/helpers.html b/user_guide/general/helpers.html
index f1aa56e..ef24e8c 100644
--- a/user_guide/general/helpers.html
+++ b/user_guide/general/helpers.html
@@ -176,7 +176,7 @@
 &nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
 <a href="#top">Top of Page</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
 <a href="../index.html">User Guide Home</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-Next Topic:&nbsp;&nbsp;<a href="plugins.html">Plugins</a>
+Next Topic:&nbsp;&nbsp;<a href="libraries.html">Using Libraries</a>
 </p>
 <p><a href="http://codeigniter.com">CodeIgniter</a> &nbsp;&middot;&nbsp; Copyright &#169; 2006-2010 &nbsp;&middot;&nbsp; <a href="http://ellislab.com/">Ellislab, Inc.</a></p>
 </div>
diff --git a/user_guide/general/libraries.html b/user_guide/general/libraries.html
index 71189df..2634b18 100644
--- a/user_guide/general/libraries.html
+++ b/user_guide/general/libraries.html
@@ -81,7 +81,7 @@
 
 <div id="footer">
 <p>
-Previous Topic:&nbsp;&nbsp;<a href="plugins.html">Plugins</a>
+Previous Topic:&nbsp;&nbsp;<a href="helpers.html">Helpers</a>
 &nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
 <a href="#top">Top of Page</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
 <a href="../index.html">User Guide Home</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
diff --git a/user_guide/general/plugins.html b/user_guide/general/plugins.html
deleted file mode 100644
index b378ea9..0000000
--- a/user_guide/general/plugins.html
+++ /dev/null
@@ -1,127 +0,0 @@
-<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
-<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
-<head>
-
-<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-<title>Plugins : CodeIgniter User Guide</title>
-
-<style type='text/css' media='all'>@import url('../userguide.css');</style>
-<link rel='stylesheet' type='text/css' media='all' href='../userguide.css' />
-
-<script type="text/javascript" src="../nav/nav.js"></script>
-<script type="text/javascript" src="../nav/prototype.lite.js"></script>
-<script type="text/javascript" src="../nav/moo.fx.js"></script>
-<script type="text/javascript" src="../nav/user_guide_menu.js"></script>
-
-<meta http-equiv='expires' content='-1' />
-<meta http-equiv= 'pragma' content='no-cache' />
-<meta name='robots' content='all' />
-<meta name='author' content='ExpressionEngine Dev Team' />
-<meta name='description' content='CodeIgniter User Guide' />
-
-</head>
-<body>
-
-<!-- START NAVIGATION -->
-<div id="nav"><div id="nav_inner"><script type="text/javascript">create_menu('../');</script></div></div>
-<div id="nav2"><a name="top"></a><a href="javascript:void(0);" onclick="myHeight.toggle();"><img src="../images/nav_toggle_darker.jpg" width="154" height="43" border="0" title="Toggle Table of Contents" alt="Toggle Table of Contents" /></a></div>
-<div id="masthead">
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td><h1>CodeIgniter User Guide Version 2.0.0</h1></td>
-<td id="breadcrumb_right"><a href="../toc.html">Table of Contents Page</a></td>
-</tr>
-</table>
-</div>
-<!-- END NAVIGATION -->
-
-
-<!-- START BREADCRUMB -->
-<table cellpadding="0" cellspacing="0" border="0" style="width:100%">
-<tr>
-<td id="breadcrumb">
-<a href="http://codeigniter.com/">CodeIgniter Home</a> &nbsp;&#8250;&nbsp;
-<a href="../index.html">User Guide Home</a> &nbsp;&#8250;&nbsp;
-Plugins
-</td>
-<td id="searchbox"><form method="get" action="http://www.google.com/search"><input type="hidden" name="as_sitesearch" id="as_sitesearch" value="codeigniter.com/user_guide/" />Search User Guide&nbsp; <input type="text" class="input" style="width:200px;" name="q" id="q" size="31" maxlength="255" value="" />&nbsp;<input type="submit" class="submit" name="sa" value="Go" /></form></td>
-</tr>
-</table>
-<!-- END BREADCRUMB -->
-
-<br clear="all" />
-
-
-<!-- START CONTENT -->
-<div id="content">
-
-
-<h1>Plugins</h1>
-
-<p>Plugins work almost identically to <a href="helpers.html">Helpers</a>.  The main difference is that a plugin usually
-provides a single function, whereas a Helper is usually a collection of functions.  Helpers are also considered a part of
-the core system; plugins are intended to be created and shared by our community.</p>
-
-<p>Plugins should be saved to your <dfn>system/plugins</dfn> directory or you can create a folder called <kbd>plugins</kbd> inside
-your <kbd>application</kbd> folder and store them there.  CodeIgniter will look first in your <dfn>system/application/plugins</dfn>
-directory.  If the directory does not exist or the specified plugin is not located there CI will instead look in your global
-<dfn>system/plugins</dfn> folder.</p>
-
-
-<h2>Loading a Plugin</h2>
-
-<p>Loading a plugin file is quite simple using the following function:</p>
-
-<code>$this->load->plugin('<var>name</var>');</code>
-
-<p>Where <var>name</var> is the file name of the plugin, without the .php file extension or the "plugin" part.</p>
-
-<p>For example, to load the <dfn>Captcha</dfn> plugin, which is named <var>captcha_pi.php</var>, you will do this:</p>
-
-<code>$this->load->plugin('<var>captcha</var>');</code>
-
-
-
-<p>A plugin can be loaded anywhere within your <a href="../general/controllers.html">controller</a> functions (or even within your <a href="../general/views.html">View files</a>, although that's not a good practice),
-as long as you load it before you use it.  You can load your plugins in your controller constructor so that they become available
-automatically in any function, or you can load a plugin in a specific function that needs it.</p>
-
-<p class="important">Note: The Plugin loading function above does not return a value, so don't try to assign it to a variable.  Just use it as shown.</p>
-
-
-<h2>Loading Multiple Plugins</h2>
-
-<p>If you need to load more than one plugin you can specify them in an array, like this:</p>
-
-<code>$this->load->plugin( <samp>array(</samp>'<var>plugin1</var>', '<var>plugin2</var>', '<var>plugin3</var>'<samp>)</samp> );</code>
-
-<h2>Auto-loading Plugins</h2>
-
-<p>If you find that you need a particular plugin globally throughout your application, you can tell CodeIgniter to auto-load it
-during system initialization. This is done by opening the <var>application/config/autoload.php</var> file and adding the plugin to the autoload array.</p>
-
-
-<h2>Using a Plugin</h2>
-
-<p>Once you've loaded the Plugin, you'll call it the way you would a standard PHP function.</p>
-
-
-
-
-</div>
-<!-- END CONTENT -->
-
-
-<div id="footer">
-<p>
-Previous Topic:&nbsp;&nbsp;<a href="helpers.html">Helpers</a>
-&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-<a href="#top">Top of Page</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-<a href="../index.html">User Guide Home</a>&nbsp;&nbsp;&nbsp;&middot;&nbsp;&nbsp;
-Next Topic:&nbsp;&nbsp;<a href="libraries.html">Using Libraries</a>
-</p>
-<p><a href="http://codeigniter.com">CodeIgniter</a> &nbsp;&middot;&nbsp; Copyright &#169; 2006-2010 &nbsp;&middot;&nbsp; <a href="http://ellislab.com/">Ellislab, Inc.</a></p>
-</div>
-
-</body>
-</html>
\ No newline at end of file
diff --git a/user_guide/general/reserved_names.html b/user_guide/general/reserved_names.html
index c9946e7..8abfbe6 100644
--- a/user_guide/general/reserved_names.html
+++ b/user_guide/general/reserved_names.html
@@ -71,7 +71,7 @@
 	<li>Default (PHP 5)</li>
 	<li>index</li>
 </ul>
-<p><br />
+<p><br /><!-- @PHP4 -->
 	If you are running PHP 4 there are some additional reserved names. These ONLY apply if you are running PHP 4.</p>
 <ul>
 	<li>CI_Loader</li>
@@ -85,8 +85,6 @@
 	<li>language</li>
 	<li>library</li>
 	<li>model</li>
-	<li>plugin</li>
-	<li>plugins</li>
 	<li>scaffolding</li>
 	<li>script</li>
 	<li>view</li>
diff --git a/user_guide/helpers/captcha_helper.html b/user_guide/helpers/captcha_helper.html
index f418823..f358af1 100644
--- a/user_guide/helpers/captcha_helper.html
+++ b/user_guide/helpers/captcha_helper.html
@@ -88,7 +88,7 @@
 	<p>The "word" is the word that appears in the captcha image, which if not
 	supplied to the function, will be a random string.</p>
 	
-	<h3>Using the CAPTCHA plugin</h3>
+	<h3>Using the CAPTCHA helper</h3>
 	
 	<p>Once loaded you can generate a captcha like this:</p>
 
@@ -139,7 +139,7 @@
 
 	<p>Here is an example of usage with a database.  On the page where the CAPTCHA will be shown you'll have something like this:</p>
 	
-<code>$this-&gt;load-&gt;plugin(&#x27;captcha&#x27;);<br />
+<code>$this-&gt;load-&gt;helper(&#x27;captcha&#x27;);<br />
 $vals = array(<br />
 &nbsp;&nbsp;&nbsp;&nbsp;&#x27;img_path&#x27;	 =&gt; &#x27;./captcha/&#x27;,<br />
 &nbsp;&nbsp;&nbsp;&nbsp;&#x27;img_url&#x27;	 =&gt; &#x27;http://example.com/captcha/&#x27;<br />
diff --git a/user_guide/installation/upgrade_200.html b/user_guide/installation/upgrade_200.html
index bf57fe3..3f6bb12 100644
--- a/user_guide/installation/upgrade_200.html
+++ b/user_guide/installation/upgrade_200.html
@@ -63,16 +63,7 @@
 
 <h2>Step 1: Update your CodeIgniter files</h2>
 
-<p>Replace these files and directories in your "system" folder with the new versions:</p>
-
-<ul>
-
-<li><dfn>system/codeigniter</dfn></li>
-<li><dfn>system/database</dfn></li>
-<li><dfn>system/helpers</dfn></li>
-<li><dfn>system/language</dfn></li>
-<li><dfn>system/libraries</dfn></li>
-</ul>
+<p>Replace all files and directories in your "system" folder <strong>except</strong> your <kbd>application</kbd> folder.</p>
 
 <p class="important"><strong>Note:</strong> If you have any custom developed files in these folders please make copies of them first.</p>
 
@@ -84,6 +75,20 @@
 
 <code>get_dir_file_info('/path/to/directory', <kbd>FALSE</kbd>);</code>
 
+</p>
+
+<h2>Step 3: Convert your Plugins to Helpers</h2>
+
+<p>2.0.0 gets rid of the "Plugin" system as their functionality was identical to Helpers, but non-extensible.  You will need to rename your plugin files from <var>filename_pi.php</var> to <var>filename_helper.php</var>, move them to your <kbd>helpers</kbd> folder, and change all instances of:
+	
+	<code>$this->load->plugin('foo');</code>
+	
+to
+
+	<code>$this->load->helper('foo');</code>
+
+</p>
+
 <h2>Step 3: Update your user guide</h2>
 <p>Please replace your local copy of the user guide with the new version, including the image files.</p>
 
diff --git a/user_guide/libraries/loader.html b/user_guide/libraries/loader.html
index bb1a983..83b3831 100644
--- a/user_guide/libraries/loader.html
+++ b/user_guide/libraries/loader.html
@@ -59,7 +59,7 @@
 <h1>Loader Class</h1>
 
 <p>Loader, as the name suggests, is used to load elements.  These elements can be libraries (classes) <a href="../general/views.html">View files</a>,
-<a href="../general/helpers.html">Helpers</a>, <a href="../general/plugins.html">Plugins</a>, or your own files.</p>
+<a href="../general/helpers.html">Helpers</a>, <a href="../general/models.html">Models</a>, or your own files.</p>
 
 <p class="important"><strong>Note:</strong> This class is initialized automatically by the system so there is no need to do it manually.</p>
 
@@ -177,9 +177,6 @@
 <p>This function loads helper files, where <var>file_name</var> is the name of the file, without the <kbd>_helper.php</kbd> extension.</p>
 
 
-<h2>$this->load->plugin('<var>file_name</var>')</h2>
-<p>This function loads plugins files, where <var>file_name</var> is the name of the file, without the <kbd>_plugin.php</kbd> extension.</p>
-
 <h2>$this->load->file('<var>filepath/filename</var>', <kbd>true/false</kbd>)</h2>
 <p>This is a generic file loading function.  Supply the filepath and name in the first parameter and it will open and read the file.
 By default the data is sent to your browser, just like a View file, but if you set the second parameter to <kbd>true</kbd> (boolean)
diff --git a/user_guide/nav/nav.js b/user_guide/nav/nav.js
index b0778cd..52d60cb 100644
--- a/user_guide/nav/nav.js
+++ b/user_guide/nav/nav.js
@@ -49,7 +49,6 @@
 			'<li><a href="'+base+'general/views.html">Views</a></li>' +
 			'<li><a href="'+base+'general/models.html">Models</a></li>' +
 			'<li><a href="'+base+'general/helpers.html">Helpers</a></li>' +
-			'<li><a href="'+base+'general/plugins.html">Plugins</a></li>' +
 			'<li><a href="'+base+'general/libraries.html">Using CodeIgniter Libraries</a></li>' +
 			'<li><a href="'+base+'general/creating_libraries.html">Creating Your Own Libraries</a></li>' +
 			'<li><a href="'+base+'general/core_classes.html">Creating Core Classes</a></li>' +
diff --git a/user_guide/overview/appflow.html b/user_guide/overview/appflow.html
index 4a1c8a3..4881fd7 100644
--- a/user_guide/overview/appflow.html
+++ b/user_guide/overview/appflow.html
@@ -68,7 +68,7 @@
 <li>The Router examines the HTTP request to determine what should be done with it.</li>
 <li>If a cache file exists, it is sent directly to the browser, bypassing the normal system execution.</li>
 <li>Security.  Before the application controller is loaded, the HTTP request and any user submitted data is filtered for security.</li>
-<li>The Controller loads the model, core libraries, plugins, helpers, and any other resources needed to process the specific request.</li>
+<li>The Controller loads the model, core libraries, helpers, and any other resources needed to process the specific request.</li>
 <li>The finalized View is rendered then sent to the web browser to be seen. If caching is enabled, the view is cached first so
 that on subsequent requests it can be served.</li>
 </ol>
diff --git a/user_guide/overview/at_a_glance.html b/user_guide/overview/at_a_glance.html
index 56f208a..be7e5e2 100644
--- a/user_guide/overview/at_a_glance.html
+++ b/user_guide/overview/at_a_glance.html
@@ -107,7 +107,7 @@
 much more.</p>
 
 <h2>CodeIgniter is Extensible</h2>
-<p>The system can be easily extended through the use of plugins and helper libraries, or through class extensions or system hooks.</p>
+<p>The system can be easily extended through the use of your own libraries, helpers, or through class extensions or system hooks.</p>
 
 
 <h2>CodeIgniter Does Not Require a Template Engine</h2>
diff --git a/user_guide/overview/features.html b/user_guide/overview/features.html
index fe0bbe9..eae9229 100644
--- a/user_guide/overview/features.html
+++ b/user_guide/overview/features.html
@@ -94,7 +94,7 @@
 <li>Unit Testing Class</li>
 <li>Search-engine Friendly URLs</li>
 <li>Flexible URI Routing</li>
-<li>Support for Hooks, Class Extensions, and Plugins</li>
+<li>Support for Hooks and Class Extensions</li>
 <li>Large library of "helper" functions</li>
 </ul>
 
diff --git a/user_guide/toc.html b/user_guide/toc.html
index 70a3f29..ff07ca6 100644
--- a/user_guide/toc.html
+++ b/user_guide/toc.html
@@ -97,17 +97,16 @@
 <ul>
 	<li><a href="./general/urls.html">CodeIgniter URLs</a></li>
 	<li><a href="./general/controllers.html">Controllers</a></li>
-	<li><a href="general/reserved_names.html">Reserved Names</a></li>
+	<li><a href="./general/reserved_names.html">Reserved Names</a></li>
 	<li><a href="./general/views.html">Views</a></li>
 	<li><a href="./general/models.html">Models</a></li>
 	<li><a href="./general/helpers.html">Helpers</a></li>
-	<li><a href="./general/plugins.html">Plugins</a></li>
 	<li><a href="./general/libraries.html">Using CodeIgniter Libraries</a></li>
 	<li><a href="./general/creating_libraries.html">Creating Your Own Libraries</a></li>
 	<li><a href="./general/core_classes.html">Creating Core Classes</a></li>
 	<li><a href="./general/hooks.html">Hooks - Extending the Core</a></li>
 	<li><a href="./general/autoloader.html">Auto-loading Resources</a></li>
-	<li><a href="general/common_functions.html">Common Functions</a></li>
+	<li><a href="./general/common_functions.html">Common Functions</a></li>
 	<li><a href="./general/scaffolding.html">Scaffolding</a></li>
 	<li><a href="./general/routing.html">URI Routing</a></li>
 	<li><a href="./general/errors.html">Error Handling</a></li>