When we are talking about search engine ranking, the first thing you need to think about is the market place. Many people ask themselves, how many keywords should I put in my anchor text? What is the keyword density that I should have on my page? Should I use 300 words on my copy or should I use 500 words? Can I use flash? How many keywords should I put in my "alt" text? Etc...

Here is a general statement: magic numbers do not exist. The most important thing you can understand as a search engine optimization expert is the following: algorithms change. Just when you think you understand what is going to make you number one for a search phrase in a search engine, something could change, and you might have to spend months or years trying to find out the engineering of the algorithm again.

It is better not to try to reverse engineer the algorithm and do something much easier instead, observe your competitors. All you need to do is to understand what elements are your competitors using that are making them rank on the top positions.

Let's see what those things are:

• Number and quality of inbound links pointing to your site

• Keyword density

• Fresh content

The first thing to observe from your competitor's sites is their back link index. This means the number of sites that have a link pointing to their website. You can easily measure it by going to Google and type: "link://www.yourcompetitorssite.com". But it would be a mistake to do this only on Google, as Google discriminates sites much more than other search engines. Yahoo and MSN are much more accurate for measuring the back link index.

Part of the observation should be not only what the links say, but where the links come from. Think on what is the category where those links come from. If you start to see a recurring pattern, you should start actively searching for links coming from that category.

Some marketers use special software for robotic content creation. They generate thousands of pages with links pointing to their sites. This practice can be dangerous, as Google may penalize unnatural linking or violations of their terms of service. And what happens is that those links do not look natural. One day one site may have 50 links and the following day have 2.050 links, which all say the same thing and come from the same IP address.

If you understand how to observe, this will never happen to you. You will learn how to look at your competitors, and observe how they are getting linked to.

The second thing you need to observe is the keyword density of your competitors. How many times should we repeat our main keyword? In which part of the web page should our main keywords be mentioned? There is no magic number, again it's all about observing and measuring against your competitors. But what should we measure?

• Meta tags

• Alt tags

• Titles

• Names of the images on the page

• Highlights: h1, h2, h3...

• Frequency and position of the keywords on the body text

Each one of these items should be measured independently. There are tools to run keyword density against your competitors. If you run them against the top 3 or 5 sites, you may start to understand the secrets of top rankings.

Again, your keyword density needs to look natural; otherwise you may fail in over optimization. This is when you use keywords too often or too early. If you look unnatural, your page ranks will suffer as a result.

The key to success is to understand what Google likes about their top 5 pages, and to apply this to your own website promotion.

The last thing to observe is how much fresh content do the top sites have. If they have many articles and they are continuously adding new content to their sites, then it is clear that the search engines like content and are ranking better those sites which have more and more updated information.

People that surf the web are usually searching for information, so content is the "fuel" of internet traffic. If you want to attract many potential customers to your site, then you need to make sure that you provide enough content which is relevant to their interests.