This plugin will allow you to add code snippets to your pages/posts. This is great for code tutorial sites.
Download the plugin, extract and upload it to your plugins folder on your server.
Activate the plugin.
Access the Code Library section.
Create a new snippet and save.
Return to the Code Library and select the "Code" link.
Copy the code.
Add or edit a page or post and paste the code into the HTML of the page/post where you want it to display.
Publish or Save the page/post.