Most business want to rank highly for the most obvious, generic, highly searched keyword phrases. These phrases are called the “fat head” phrases. While they do get many searches each day, they only account for 30% of all searches.
The other 70% of all searches are “long tail” searches. Long tail keyword phrases are typically 3+ words long and are very specific. They are much more specific than fat head phrases. As a result, long tail keywords often convert better, because they catch people later in the buying/conversion cycle. Long tail keyword phrases are easier to rank highly for in natural search and they are generally less expensive per click in a Pay-Per-Click campaign.