We don't use the meta keywords tag on any of our sites, but people often wonder why. Here's a lowdown...
What is the meta keywords tag?
Look at the code behind some websites and near the top you'll see something beginning with <meta name="keywords" content="[lots of keywords]"> - this is known as the meta keywords tag. Early on in the web, website owners used it to help search engines identify keywords they'd like their website to be associated with, but, like everything search-related, it didn't take long before people started abusing it. As search engine technology improved, the meta keywords tag lost relevance. Not only were search engines better able to identify their own keywords but the widespread abuse rendered it pretty much useless.
Is it worth bothering with?
No, and it could actually hurt you. A while ago, Google announced they would not be using the keyword tag.1 Google's dominance in the UK, especially, means it's not worth bothering with the keyword tag then. Interestingly, Bing have actually gone even further. Not only have they indicated they don't use it rank websites,2 they've concluded that spammers often use the tag excessively so have gone one step further and advised people not to use it!
Basically, don't use the meta keywords tag, and if someone says you should use them help them out and show them this article (or the links in the footnotes).