The meta keyword tag appears in the header area of a web site and is therefore not visible on the page but can be seen in the source code. Along with the title of the page and the meta description, the meta keyword tag has traditionally been used by webmasters and SEO experts to aid search engine ranking and position. As you might imagine from the name of the tag, the contents of the meta keyword tag are a simply list of keywords relevant to the page in question. Usually they are a list of the most important words on the page separated be either a comma or just a space and may include keyword combinations, plurals and sometimes misspellings, all as an aid for the SEO and search engine to indexing this particular page.
The keywords are written as the quote enclosed value of the keyword meta tag's content attribute as follows:
<meta name="keywords" content="your, keyword, crammed, comma, separated,
list, goes, here" />
Cramming, spamming and repetition.
The meta keyword tag was possibly the most abused tag on the web. In the early days of internet search engines, the search engine spiders and robots would scan the meta keywords as a quick and easy way to index the page. This was soon picked up by unscrupulous webmasters who crammed the tag full of often irrelevant words, including all sorts of useless combinations with misspellings, repetition, and in some cases words that were highly searched for adult terms which did not actually appear on the page. This could result in an increase in visitor numbers for the very short term, but if the viewer was searching for something totally different the only result was frustration and disappointment.
If you have nothing better to do with your time, by all means include a meta keyword tag on the pages of your site. However these days search engines use many other factor when deciding on the ranking and positioning of a particular page in the search results, and there is a growing feeling in the SEO community that the meta keyword tag is ignored completely. Indeed cramming the tag full of irrelevant content may do more harm than good. You are better advised to create some more unique content for your site rather than spend time with the meta keyword tag. In fact, if you view the source code of this very page you will not find a meta keyword tag.