The way that meta tags and meta data has been used by search engines has changed dramatically over the last dozen years. Meta data, for those who are uninitiated roughly means data about data. Meta tags, in theory, are one of several tools that search engines and other clients use to return results in searches. How much time should you spend on writing meta tags and meta data? For the purposes of organization Meta will be divided into three categories: Keywords, Tags, and Other Meta. Several articles about the demise of Meta Keywords have been written in the last couple of years. Google announced a while back that they no longer use meta tag keywords. Bing and Yahoo do, however, use keywords as one of several hundred published criteria. Key words are, by most expert assessments, the least valuable of meta data. While they may assist in some search engine optimization, the best way to get your webpages in search engines is to use wording in the body of the email that contains they keywords that you would normally use in meta. How much time should you spend on keywords? Not much. If you are low on time or energy this is the first thing that you should drop.
Tags are also meta data that is used in web searches. They help to categorize your content much in the same way that keywords used to. Google has a great page for usage of these items that tell browsers and search engines what to do with the data that it sees on your web site. You can leave instructions to not index information, not provide alternative descriptions, and not to cache your website. You can also set up links for translation to other languages.
Title and description is essential meta data. If you are using a WYSIWYG editor such as Word Press or Joomla the Title and Description are automatically embedded into your HTML as you fill out the handy fields that are provided to you. The description of any page returned through search is displayed as a snippet in the results. This text is sometimes truncated depending upon the search engine and settings on your computer and the length of the description.
For more information about Meta go to the W3 website. In fact even if you aren't interested in Meta Data you should probably go to the W3 website and familiarize yourself with the content. Anyone who has a website should be aware of W3 and the tools and information available.