How do I disallow spiders?

I want to know what code to put on a page to not allow spiders to crawl.

[Mitch]

I already know about having a robots.txt file in the root directory of a site which tells spiders not to crawl certain areas. But, what code can I put on a web page that would disallow spiders from crawling it? Thanks for any feedback.

[lazerzubb]

I guess you're looking for this
[robotstxt.org...]