Meta tags are not a magic solution. Meta tags provide a useful way to control your summary in some search engines. The search engines that support meta tags can be found on the Search Engine Features page. The More About Meta Tags article available to Search Engine Watch members provides more information about meta tags, including specifics for particular search engines and strategies about writing them. Click here to learn more about becoming a member Meta tags can also help you provide keywords and descriptions on pages that for various reasons lack text.
Examples are splash pages and frames pages.
They might also boost your page's relevancy. However, simply including a meta tag is not a guarantee that your page should suddenly leap to the top of every search engine listing. They are a useful tool but, as said above, not a magic solution. There are several meta tags, but the most important for search engine indexing are the description and keywords tags. The description tag returns a description of the page in place of the summary the search engine would ordinarily create.