This is so complex because there are many different search engines and they use different methods to perform a similar task. And, with ever-changing technology and software advances, what is the rule for today may not be useful tomorrow.

First of all, let's start by answering the question, "What is a search engine?"

Internet.com defines a search engine as "a program that searches documents for specified keywords and returns a list of the documents where the keywords were found."

In other words, when a Web site user is looking for information, they can go to a search engine Web site, type in specific words and the search engine will return a list of Web sites that it thinks matches what the person is looking for.

Knowing that huge numbers of people are going to search engines and performing all kinds of searches, this is a resource that commercial Web sites can't ignore. Getting your Web site listed with search engines is one of the first things people tend to do after developing a Web site.

However, it is not the only thing that commercial Web sites can do. It is important to note that successful Web sites need to be marketed and should have a marketing plan. How this is done varies from business to business and search engines are just one tool that should be used in conjunction with other marketing methods.

Now, as I said before, search engines are nothing more than Web sites that allow you to search though catalogs of information and give results based on that search. This means that there are many different search engines competing for your business. In fact, there are hundreds, even thousands out there.

But, over time, a few have moved to the top, and several others have formed relationships where they share information, which creates a more powerful resource for each of them.

Therefore, because only a few search engines and resources are handling almost all of the Internet's searches, submitting your site and getting it listed in four main Web sites will maximize the traffic that search engines can drive to your business.

Before discussing each of these, it is also very important to note that having a site designed and optimized for the search engines is very important and businesses need to be sure that their sites have done this before beginning the registration process.

While technical, it is important to mention a few of these essential elements that will make your site more search-engine friendly. To begin with, your site should have a clean layout without the use of unnecessary frames. The Web site title and text should be clear and descriptive, using keywords associated with your business. Finally, in the html code of the Web site, meta tags should be used to include keywords and descriptions and alt text should be used in place of any images or graphics that appear on your pages.

Currently, the reigning search engine king is Yahoo! (http://www.yahoo.com). And, they know it. They became so popular that they couldn't handle all the submissions from people trying to get listed in their database. About a year ago, they capitalized on this and began offering a fee-based service where they would review your site within seven days for $150.

They have continued to grow and today, they require that all commercial Web sites pay $299 to get listed in their site. Unfortunately, the amount of traffic that Yahoo! can build for commercial Web sites is significant and it is essential to be a part of their resource.

Yahoo! has also partnered with another of the big four called Google. After a search is done from the Yahoo! home page, you will get the results from the Yahoo! database. Then, you will see matching Web pages based on the Google directory but still within the Yahoo! site.

So, in some respects, getting listed with Google gets you into Yahoo!. However, because those results are displayed after the main Yahoo! database results, this is only a partial success and should not be considered an acceptable solution.

As I just mentioned, the next major search engine is Google (http://www.google.com). The good news about Google is that it is free. However, after submitting your site to them, it takes about eight weeks before you will begin showing up in their results.

Google does have the ability to drive a lot of traffic to business Web sites, but the company's biggest asset and reason for being part of the big four is it's relationship with Yahoo!, where their database appears after the other Yahoo! category listings.

The third search engine that can't be ignored is MSN. Because of the MSN Search integration as the default when you hit the search button in Internet Explorer, the MSN database is being used by huge numbers of people without them even realizing it.

But, you can't submit your site directly to MSN (http://search.msn.com). As I stated above, this is an example of a search engine who uses a shared database and is partnered with multiple search engine sites.

So, to get into MSN, you must submit with LookSmart (http://www.looksmart.com). And, like Yahoo!, LookSmart is now charging for their service. It costs $299 to have a site reviewed within two business days or $149 to have it reviewed within eight weeks.

The good news is, when you are added to this database, your site will be displayed in searches on MSN, Excite, AltaVista, iWon.com and CNN.com, all of which are reputable resources that can drive additional traffic to your site.

The fourth search engine resource that can make a major difference in the traffic to your site is called the Open Directory Project (http://www.dmoz.org).

This resource is free to use and, while it isn't the most popular site with people doing searches, it supplies the database to other resources who are more popular with people doing general searches.

New site submissions are usually added fairly quickly to dmoz, and they claim it takes an additional 2 weeks to several months for your site to be listed on partner sites, which include AOL Search, AltaVista, HotBot, Google, Lycos and Netscape Search.

Another tip for the business who wants to really get the edge on their competition and show up first in the search engines is a new service being offered where you can buy better results.

Yahoo! calls this "Sponsored Sites." Basically, you pay based on how many people view or click your link which keeps the search engine motivated to display your site before non-paying customers and in a more prominent fashion, often bold or outlined. Many sites offer this service and you should visit the one you are interested in advertising on for prices and options.

It is also important to watch out for services claiming to submit your site to 500 or 1000 search engines for a small fee. Most of the time, these companies are profiting by collecting your personal information and selling it to marketing companies who use your e-mail address for spam and other solicitations.

Remember, it has been proven that almost all traffic that comes to your site through the search engines will use one of the main search resources listed above. Trying to maintain your listing in hundreds of search engines is a pointless and futile effort.

The last, most important tip to remember is after spending all this time and money to get people to your site, make sure you provide a resource that will fulfill their needs and make them want to come back again.

This includes developing a unique and professional Internet presence that will represent your company well and to provide information, services and resources that meet your customer's needs.