Flash animation is one key element that makes a webpage stand out. It can be used for almost anything in a web page, but can either increase or decrease a users ability to interact with your website.

For example if you have a lot of information where people may need to copy and paste - it would be ideal to make your Flash in XML or to make it in standard HTML so that they can; normally flash prohibits that behavior. On the other hand, flash is wonderful for making users interact with the webpage and creating "flashy" animations or movement. It is very much a project by project decision.