The Google Business Places listing is the map that comes up when you do a search for a business in Google.
It usually gives you a map with some red flags on it, these flags usually have letters A, B, C etc etc which correspond to the business name listing.
If you have a business and your clientele is mostly local, it's definitely worth setting up a business place (and I would consider a Google+ page as well).
Here's a link to Google's support page on setting up your business place listing.
If you need any help or advice with setting up your business listing, send me an email on firstname.lastname@example.org.