The Keywords interface allows you to create or manage your list of keywords (to a maximum of 15) which are submitted to search engines. If you get stuck, it also suggests alternate keywords which may be relevant.
Note: Keywords are important, but if too many are used, or if they are used in order to try to "catch" people searching for information which is unrelated to your website content, then search engines typically refuse to list the site. Essentially, the role of keywords on a website is to provide a short, relevant list of popular words that are commonly used to search for the content contained on your website. For consistency, it is also essential to use these same keywords in your website content; depending on the search engine, using keywords which are not used in your website can be as detrimental as keywords which are completely unrelated to your website.