With the box checked, you will get focused search results for this web site.
If you uncheck the box, you will get the Google search results that you are used to getting when you use Google.com.
With the box unchecked you can also use the search box as a calculator. See Calculating Tips ...
In the following method, you add the destination on the Google maps page. Results are sometimes slightly different. The method above tends to assign a business to an address. The method below is known to assign the pure address.