Linking to a specific page

Okay, so I was wondering if there is a way to dynamically link to a page.

I’m building a theme and I’d like the option to link to an ‘About’ page, but I want the link to be pulled dynamically. So if the client changes the name, the link will follow suit.

For instance, something like ‘page_url(‘about’)’ about be useful.

I looked around for an answer, but to no avail.

Any help is much appreciated. Thnx!!
DB