Keyword suggestion tools help you understand what words are used in search queries and what phrases are associated with those words. Keyword analytical tools provide some measure of keyword suggestion functionality, as well as the ability to understand the competition levels for specific search terms. More importantly, keyword analytics tools help you determine the relative size of the search referral market associated with specific keywords and phrases.

Read more about keyword analytics tools and how effective they might be for your site in this article at ClickZ here.

From Google Trends to Quintura, get an inside look at these free keyword suggestion tools that can help you with content optimization for your site. Read the full review of these tools at ClickZ here.

So how can you know what’s popular with searchers and what is not? The process of keyword research involves using some online tools to estimate the popularity of keywords with searchers, and then taking into account the competition for the top rankings for those keywords.

A good place to start with your research is to check the popularity of keyword searches using Overture’s Keyword Selector tool, which is a free tool available at inventory.overture.com. This tool is based on data from all searches on Yahoo! over the past month as well as other Yahoo! Search Marketing partners. While this is a huge amount of free data, the downside is that verb tenses, plural and singular forms, and misspellings are all aggregated together. What that means to you is that when using this tool you have no sense of how popular a variation of a keyword (such as a misspelling) is in comparison with the main form of the word. This can be especially frustrating if you have no sense as to how popular the plural form of a noun is versus the singular form.

A good rule of thumb is that the plural form is usually more popular than the singular form. However this is not always the case, and the degree to which that varies depends on the keyword.

Another free tool to find keyword popularity is Google’s Keyword Sandbox, available at google.com. One drawback to this tool is that it doesn’t actually return any hard numbers like the Overture tool, but it does have a place in your keyword research arsenal. Though the results of your keyword search are displayed in order of popularity, the absence of quantitative data makes it difficult to compare relative popularities in any meaningful way.

Despite its limitations, the Google tool does allow you to localize your searches based on country and language, which is a valuable tool for businesses with international sales. In addition, the Google tool will also distinguish between singular and plural forms of a word, verb tenses, and misspellings, giving you an idea of how popular each form of your keyword is. Not to mention that the Google tool is based on data collected from the largest sample of Internet searchers on the planet: the users of Google.

When it comes to selecting the best keywords, these two tools really only get us part way, but the price was right! In order to get serious you will have to part with some hard earned cash by buying a subscription to WordTracker.com (about $260).

WordTracker overcomes the verb tense, singular verses plural, and misspelling limitations of the Overture Keyword Tool. In addition it offers advanced functionality such as the ability to build projects that contain groups of keywords that you can do research on, import into Excel, and search for synonyms.

WordTracker’s database is based on searches done on the meta search engine MetaCrawler, a search engine owned by Infospace, over the last 130 days. While MetaCrawler is a minor search engine and accounts for less than 1% of the search market, there is still enough data to get statistically significant comparisons between the popularity of various keywords.

Additionally, WordTracker calculates a Keyword Effectiveness Indicator “KEI,” which allows you to take into account not just keyword popularity, but also competition for that keyword. A KEI score is simply a ratio of keyword popularity to the number of search results returned for that keyword. KEI scores are specific to each search engine, and you should run KEI scores for at least Google and Yahoo!. The higher the KEI score the more attractive the keyword is to target, assuming of course it is relevant to your business.

Using the aforementioned tools you should be able to find some great keywords that are relevant to your business and popular with searchers. However, remember that achieving a high ranking for certain keywords may not be feasible if there is a lot of competition and/or the competition is SEO savvy.

This article appeared in the November 2005 issue of Practical Ecommerce magazine.