Keywords are the words that web surfers enter in search engines to find
websites. It's pointless to optimize your web pages for keywords that
nobody uses in the search engines.
For a successful online marketing campaign, you must target the right keywords. The keywords you use should be relevant for your website and web surfers should be searching for your keywords.
If you target the wrong keywords, your website promotion efforts will be in vain and you will waste a lot of time and money.
There are three different keyword types: keywords for browsing, keywords for comparing and keywords for buying.
Keywords for comparing are usually the keywords that work best for search engine optimization. People who use that keyword type are looking for a solution to their problem and they are ready to buy. To get best results with your search engine optimization efforts, you should concentrate on that keyword type.
Most people use a two to four word phrase in a search, so phrases are very effective. Single words cannot be promoted effectively because they are not very targeted. Internet users who use four-word searches are more likely to purchase goods or services than those using fewer words (source: Oneupweb Research).