When building a keyword list there are three primary goals.
1.Find commonly used niche keywords and keyword phrases.
2.Find commonly used niche keywords with little competition.
3.Find uncommonly used keywords with some consistent volume of search and little competition. These types of keywords or keyword phrases are known as “long tail keywords”.
When you offer online services, it is best to target both broad based target keywords as well as more focused long tail keywords. As a site begins to rank for long tail keywords, its competitiveness for the broader keywords will begin to increase. As you begin to rank higher for the less competitive long tail keywords, those higher rankings will pull up your rankings for the tougher, more competitive terms.
The more topically relevant keywords and phrases that you rank for, the more competitive you become for the parent term. Moreover, if you ignore either category of keywords you may loose potential customers. The general idea is don’t trip over the less trafficked keywords to get to the more heavily trafficked keywords. Add the less competitive, lower yield, long tail keywords and, in the long run, you will rank and convert better.