Once you have your small business website up and running, no matter how good it is, if the search engines don’t know it exists, nobody else does either. You can of course advertise it, and that will do worlds of good, but the best advertising you can get won’t compare to a high rank in a search engine.
That is where search engine optimization comes in. Search engine optimization is optimizing your website for ranking in search engines. And if you do a good job with that, you’ll end up with a place on page 1 of the relevant searches, which is the best place to be.