Meta tags

Meta tags are special HTML elements which increase your site visibility.Recently,it is said that meta tags are dead and that they are of no use.But still a large group of web masters do believe that meta tags significantly increase search engine visibility of websites.
Meta tags are more useful in social bookmarking though they might have lost their impotance in SEO.

You can find many Meta tag Generators available on net for free.Create your meta tags in one of these sites which build you your site's meta tags and copy paste the code in your template html.
If you are a Blogger(like me), am sure you would get this 'error' message when you try to save your meta tags in your template - Your template could not be parsed as it is not well-formed. Please make sure all XML elements are closed properly. XML error message: The element type "meta" must be terminated by the matching end-tag "". This is because Blogger uses XHTML and not just HTML.You need to terminate each line starting with "meta" with />.

Example - [meta name="whatever" content="good"/] This is how each line starting with "meta" should end.
Note: In the above example,Replace the parenthesis - [ ] with < > (so each line should end with />)

An article about XHTML and HTML