Search engines look at your document structure and text. The age of meta tags are gone, and meta description mostly ignored or rarely used.
Wouldn't it be nice, if you could actually see what the search engine sees? Well, you can.
(You need Firefox to see this – any version will do)
How to see
- Visit your target page or take a random pick, i.e. http://en.wikipedia.org/wiki/HTML
- In your browser menu, open View -> Page Style and choose No Style
(To undo, repeat the process, but choose "Basic Page Style")
What to look for
- Look for headings, such as <h1> and look at the structure.
- Does images appear right above/below the text they relate to?
- Do headings correctly emphasize the section that comes below? Headings can be used for sections, so the engine knows what comes next. Use important and relevant keywords in the heading.
- Does the structure of your menu appear clearly?
- When you are listing something, does the lists appear correctly, indented with bullet points?
- Does tables appear clean without specific layout? Headers would usually appear clearly in bold and regular table cells (table data) should appear without visual formatting.
- Would your page be mostly functional without the stylesheet? Usually, it should be.
When you disable the stylesheets as described above, it means you will see how the document looks to the search engine*. Search engines ignore stylesheets, so this will give you an idea what they see.
* What you see is actually your browsers default stylesheet, but coincidently it emphasizes the important elements