Customise WordPress Admin Footer

Watch out! This tutorial is over 8 years old. Please keep this in mind as some code snippets provided may no longer work or need modification to work on current systems.
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Change the message that appears in the admin footer, why not give yourself a credit for the theme?

// Customise the footer in admin area
function itlc_footer_admin () {
	echo 'Theme designed and developed by <a href="#" target="_blank">YourNameHere</a> and powered by <a href="http://wordpress.org" target="_blank">WordPress</a>.';
}
add_filter('admin_footer_text', 'itlc_footer_admin');