Building a new website? Flash can surely help you bring breath-taking animations and eye candy effects to your visitors but if there is no one to see your creation, do you think it’s worth building then?
That’s right if you want a major chunk of traffic coming from search engines like Google forget use of Flash objects. Flash and SEO are like Oil and Water, they do not mix and never like each other. Google rates websites largely based on the content present within and they have custom made software that act like bots to scan the content available on each and every page. Unfortunately, their software or any software for that matter could not decipher what’s within the Flash object and so your website content is missed in their scanning process.
Using Flash objects will not just have an impact on search engine ranking but also on your visitors because of their larger file size, they take too long to load and no one would like to wait until it loads. They will instead move on to another site that gives them just what they need.
However, you can still use Flash for menu items, video presentations and some minor bits on your website; provided you assign alternate html content for the same so the search engines could decipher them. But the main content or the meat should always be in plain text which can further be stylized by the use of CSS codings.
Same principle applies for use of Silverlight and other technologies that may work similar to Adobe Flash on bringing eye candy effects.