jesucarr

The main reason for the development of this plugin was the lack of options supporting the HTML5 recommendation, where the code snippets should be tagged with <code>pre</code> followed by <code>code</code>, and optionally a class starting with <code>language-</code> and then our language.
You can use the plugin like this:
<pre><code><pre class="prettyprint"><code class="language-php">
// my code
</code></pre>
</code></pre>
Also very important is that although this plugin loads different files depending on your configuration, it fully supports caching scripts (<a href="https://wordpress.org/extend/plugins/w3-total-cache/" rel="ugc">W3 Total Cache</a>) to concatenate and compress all the css and js, so the impact in performance will be minimum.
<h4>Languages</h4>
This syntax highlighter is based on <a href="http://google-code-prettify.googlecode.com/svn/trunk/README.html" rel="nofollow ugc">Google Code Prettify</a> and should work on a number of languages including C and friends, Java, Python, Bash, SQL, HTML, XML, Javascript, Makefiles, and Rust. It works passably on Ruby, PHP, VB, and Awk and a decent subset of Perl and Ruby, but, because of commenting conventions, doesn’t work on Smalltalk.
Other languages are supported via an extension (plugin options): CSS, SQL, YAML, Visual Basic, Clojure, Scala, Latek (TeX, LaTeX), WikiText, Erlang, Go, Haskell, Lua, OCAML, SML, F#, Nemerle, Protocol Buffers, CHDL (VHDL), XQ (XQuery), Lisp, Scheme, Dart, Llvm, Mumps, Pascal, R, S, RD, TCL
<h4>Styles</h4>
Four different styles are provided, and they can be previewed in the plugin options. They are modified to make sure they don’t clash with any other styles in your theme.
You have also the option to include your custom style.
If you have a style that would like to see included in the option list, just <a href="http://www.frontendmatters.com/contact/" rel="nofollow ugc">contact me</a>, or <a href="https://github.com/jesucarr/wordpress-prettify-code-syntax" rel="nofollow ugc">fork me</a>.
<h4>Notes</h4>
<ul>
<li>
Plugin options are at Settings > Prettify Code Syntax. Have a look at the Screenshots tab to see how it looks like.
</li>
<li>
If you don’t care too much about the HTML5 recommendation, you can skip the <code>language-</code> class. The code always gets detected automatically.
</li>
<li>
It will also work if you only use a <code>pre</code> tag without the <code>code</code> tag (but long lines will be wrapped instead of get horizontal scroll), or if you only use a <code>code</code> tag with the <code>prettyprint</code> class (but if you don’t use <code>pre</code> your spaces/returns won’t be maintained.)
</li>
<li>
Be careful using the Visual Editor tab when inserting code, as some HTML tags will be modified or removed.
</li>
<li>
Using a chaching plugin like W3 Total Cache is highly recommended.
</li>
</ul>
<h4>Demo</h4>
You can find a <a href="http://www.frontendmatters.com/open-source/wordpress-plugins/prettify-code-syntax/" rel="nofollow ugc">front end demo</a> here a the bottom.

Prettify Code Syntax

Code syntax highlighter using Google Prettify, supporting the HTML5 recommendation, and caching plugins.

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This plugin has prettify.js copied directly from google-code source browser. So your code will look exactly like it does on google-code. 
CSS is slightly modified to embolden keywords and types.
<h3>License</h3>
See prettify.js for license details (Apache License 2.0). Other files are available under GPLv2.
<h3>Usage</h3>
<pre class="prettyprint"> 
 // Put your code here. 
</pre>
Or with shortcode:
[code] 
 // Put your code here. 
[/code]
<h3>Making Code HTML Safe</h3>
The plugin automatically makes highlighted code html-safe:
<pre class="prettyprint"> 
 Anything that goes here will be quoted to appear on the page as-is. 
 For example: <head></head><body></body> 
</pre>
To avoid quoting your code, add dontquote as the first class.
<pre class="dontquote prettyprint"> 
 Remember to quote manually. 
 For example: &lt;head&gt;&lt;/head&gt;&lt;body&gt;&lt;/body&gt; 
</pre>
<h3>Line Numbering</h3>
Line numbdering can be enabled as follows:
<pre class="prettyprint linenums"> 
 // Put your code here. 
</pre>
If you want to start with a line number 42, you can do the following:
<pre class="prettyprint linenums:42"> 
 // Put your code here. 
</pre>
<h3>Highlighting Lines</h3>
When line numbering is enabled you can highlight one or several lines of code using the highlight class:
<pre class="prettyprint lang-YOURLANG linenums highlight:2,4"> 
 // line 2 
 // line 3 
 // line 4 
</pre>
Alternatively you can highlight one or several code segments:
<pre class="prettyprint lang-YOURLANG linenums highlight:1-3,5-6"> 
 // line 2 
 // line 3 
 // line 4 
 // line 5 
</pre>
Note: This feature is not available when line numbering is disabled.
<h3>Specifying Language</h3>
Most of the time the highlighter will do a good job guessing how to highlight the code. However, to achieve the best result, you should specify the language:
<pre class="prettyprint lang-YOURLANG"> 
 // Put your code here. 
</pre>
Replace YOURLANG with one of the following:
<ul>
<li>aea</li>
<li>agc</li>
<li>apollo</li>
<li>bsh</li>
<li>c</li>
<li>cc</li>
<li>cl</li>
<li>cpp</li>
<li>cs</li>
<li>csh</li>
<li>css-str</li>
<li>cv</li>
<li>cxx</li>
<li>cyc</li>
<li>default-markup</li>
<li>el</li>
<li>fs</li>
<li>go</li>
<li>hs</li>
<li>htm</li>
<li>html</li>
<li>java</li>
<li>js</li>
<li>json</li>
<li>lisp</li>
<li>lua</li>
<li>m</li>
<li>ml</li>
<li>mxml</li>
<li>perl</li>
<li>pl</li>
<li>pm</li>
<li>proto</li>
<li>py</li>
<li>rb</li>
<li>scala</li>
<li>scm</li>
<li>sh</li>
<li>sql</li>
<li>vhd</li>
<li>vhdl</li>
<li>wiki</li>
<li>xhtml</li>
<li>xml</li>
<li>xsl</li>
<li>yaml</li>
<li>yml</li>
</ul>
<h3>Shortcode</h3>
Here is a quick example. All the parameters are optional.
[code lang=”scala” start=”1″ highlight=”1-3,6,10-14″ background=”#C0FFB3″] 
 // Put your code here. 
[/code]
Html quoting can be disabled as follows:
[code quote=”false”] 
 // Put your code here. 
[/code]
The contents of shortcodes is auto-formatted by WP. As a result and tags along 
with some formatting will be lost. If you need to preseve the original formatting use 
html notation instead of the shortcode.
<h3>Please Support</h3>
If you like Prettify GC Syntax Highlighter plugin, please donate a minute of your time and vote for it. Thank you!

Prettify GC Syntax Highlighter

Your code will look exactly like it does on google-code.

Prettify Code Syntax vs Prettify GC Syntax Highlighter