Meta Tags are very important for your website's visibility. Many search engines read them from your site when you submit it to them .Major meta tags that you can use:

The only resource type that is currently in use is "document" This is the only tag that you need to put in for indexing purposes.

Depending on the search engine, this will be displayed along with the title of your page in an index. "content" could be a word, sentence or even paragraph to describe your page. Keep this reasonably short, concise and to the point.

Choose whatever keywords you think are appropriate, seperated by commas.

at the right or at the bottom, but not on the left, of the page.  When the search engines "read" your site, they read from the top left to the bottom right.  Search engines place an emphasis on the first 100 words or text on the site.  You do not want these words to be navigational links or Javascript.  Ideally, you want to have your heading tags with your keywords in the beginning of your page.  This being said, placing your links/JavaScript on the right or bottom of your page ensures the search engine spiders get to the text first, giving more weight to what's important on your page.

The more content you have on your site the more likely someone is to find what they're looking for when they get there. Keep your site very content rich. Have a lot of pages.Update the site even twice a day if you have the time. Updating your site does not mean that you copy paste content from other sites.That will only push your rankings further down. Don't have any duplicate content. At the same time ,dont spam multiple content across the same website. When a search engine views or reviews a website, which they do at least every few months, it looks for specific characteristics found in the content of website landing pages.

As you read ebooks, blogs and forums about Internet marketing you'll come across all kinds of advice. From the number of times you should repeat a keyword in an article to the number of words that your webpage should have on it. (1-3% and 500 words are common suggestions). From the supporting words you should use on page to whether you should bother with meta tags.

But how do you know if all that well-meaning advice really reflects what the SE's want?