AdWords is probably the most popular method of pay-per-click advertising. Microsoft adCenter and Yahoo Search Marketing are other top pay-per-click vendors.

The basic idea is that certain search words are relevant to your business, and when prospective customers enter these words into search engines, a link to your business will appear on the search results page.

The more you pay for a particular word or phrase, the better the chance you have of appearing on page one of someone’s search results. Also, whenever you do appear there, if someone (the searcher) clicks on your link, Google (or whomever you purchased the pay-per-click service from) will charge you for it (thus “pay-per-click).

You pay for each time someone clicks through to your page. If you notice on the Google search results page, several links appear at the top and side of the page, these are the pay-per-click businesses; they have paid Google to appear on page one.

The only drawback to this particular form of advertising is that you essentially have no control over the quality of the click-throughs (those prospects who click on the Google AdWords links in the Google search results). You could have a devious competitor who hires a computer programmer to design a program that would do searches automatically on Google each day and click-through to your site. You would then be charged for all of these click-throughs and they would all be worthless to your business. As a result, your competitor has used a devious tactic to disrupt your business. But when you think about this possibility, you will eventually realize that competitors can do this in other ways as well (programs that tie up your phone lines), so the vulnerability is not unique to AdWords.