linking to outside Web address

I already have a Web site and would like to link back to my home page from the sidebar of my WordPress blog, rather than linking to another internal page on the WordPress template. Originally the template had a header in the sidebar that said “Pages,” and under that a link that said “About,” which links to another internal page. I changed “Pages” to say “Back to Web site,” and changed “About” to say “Home.”

I think I have pinpointed that I have to do something to the line of code in the “sidebar” template that says: <?php wp_list_pages(‘title_li=<h2>Back to Web site</h2>’ ); ?> But I don’t know php, so am not sure what to do to it so I can insert the link to my home page.