The Custom Code settings is one of the three ways you can add custom CSS to your site. The other methods for adding custom CSS are the PageLines Customize Plugin & the Base Theme. You also use the Custom Code Settings to add Header & Footer scripts and Analytics.
From your WordPress Administration Panel:
This setting is a simple quick way to add custom styles to your site without having to edit any css files. Anything you enter here will be saved to your database. Always remember to backup your database.
Even though using this Custom CSS setting will give you the results you are looking for, is easy to use, and is considered perfectly safe, it is not necessarily considered to be the best, or most "professional" method for adding CSS to your site. If you are adding more than just a few simple lines of CSS, and would like to use a more professional approach, we recommend using either the PageLines Customize Plugin or the Base Theme, both available for free in the PageLines Store.
For more information on CSS & how it relates to PageLines 2.0, click on Custom CSS
This is where you insert any footer script, including Google Analytics.
For more information, click on http://www.google.com/analytics
This is the placeholder for Google asynchronous analytics. It goes underneath body tag.
For more information, click on http://code.google.com/apis/analytics/docs/tracking/asyncUsageGuide.html