When you design for search engines, when you design for people

Improved SEO documentation galore!:

I’ll run through 3-4 quick examples of things that are perfectly okay to do for search engines, but that you wouldn’t automatically do for users:

• Adding a nofollow attribute to a link doesn’t affect users, but can serve as a useful indicator to search engines that you don’t necessarily want PageRank to flow through that link.
• Adding a meta description. When a user visits a web page, their browser doesn’t show the meta description data in any way. But you can suggest to search engines to show a particular snippet by using the meta description wisely.
• You can tell Google your preference on www vs. non-www. Again, that’s probably not something that users see or that directly affects them, but it’s still a smart thing to do.
• Submitting a Sitemap to Google or making it available to other search engines is not an action that you’d take for users, because users don’t see Sitemaps. But it can be a smart move because search engines can do better if you provide that information.