How to research Google Keywords for more traffic

Through the detective work of puzzling out your market's keyword demand, you not only learn which terms and phrases to target with SEO, but also learn more about your customers as a whole. ...  The usefulness of this intelligence cannot be overstated - with keyword research you can predict shifts in demand, respond to changing market conditions, and produce the products, services, and content that web searchers are already actively seeking.

...The keywords visitors type into search engines are often available to webmasters, and keyword research tools allow us to find this information.

...Understanding which websites already rank for your keyword gives you valuable insight into the competition, and also how hard it will be to rank for the given term.

...If your website doesn't rank for the keyword, you can nonetheless buy "test" traffic to see how well it converts.

...For example, if your search ad generated 5,000 impressions, of which 100 visitors have come to your site and 3 have converted for total profit (not revenue!) ...  Those 5,000 impressions in 24 hours could generate a click-through rate of between 18-36% with a #1 ranking (see the Slingshot SEO study for more on potential click-through rates), which would mean 900-1800 visits per day, at $3 each, or between 1-2 million dollars per year.