There is an old marketing rule that in any mature market there will only be two big players. The first will have 50% of the market, the next 25%, and everyone else will split the rest.

Except online.

On the web, you must remember domain names to type into the location field. There is no Coke and Pepsi sitting on a shelf. Instead, you must remember the brand you want and ask for it by name.

The way most people deal with this is learn one domain name that can substitute for each category. It becomes almost automatic. As your fingers hover over the keyboard with your cursor in the location field on your web browser, you will inevitably type the name of the domain that serves as your mental substitute for the category you want.

We all do it. When you think books, you type Amazon. When you think portal, you type Yahoo. And when you think search, you type Google.

Once one domain becomes the dominate substitute for a category, it picks up steam and pretty soon it is the only one almost anyone can remember. The category has been won.

Now, Google has won the search category. For most people, it is the substitute for “search”. In fact, Google has done so well, it has slipped into the general lexicon. How many times have you heard someone say “I googled it” when they meant “searched?”

So, Microsoft is desperately trying to get their foot into search. They bid for AOL’s business. They announced new search technologies. They even considered paying users to use their search site.

Unfortunately for them it’s a losing battle. Google means search in the mind of most users around the world. Google has won the general search category. Microsoft lost. Game over.

Or is it? As it turns out there is a way that Microsoft could compete with Google’s dominance. It’s a tried and true tactic that has worked many times before and Microsoft (or anyone else) could do it for themselves if they wanted.

I’ll get into the strategy they could use tomorrow.