Let's take a look at how to create a Google Maps layer.
From this point onward, I'm going to assume that when I say "create a new map" you will use the template from http://vasir.net/openlayers_book/, or create a copy of the example from Chapter 1 and remove the WMS layer calls (they both result in the same code). So, create a new map.
The first thing we'll need to do is add in a script tag to the <head> section that references the Google API library. This allows us to actually use the Google Maps library: