Flash has several strong advantages
Animation
Indeed, animation is the very first thing that pops up in your mind whenever you hear 'Adobe Flash' Flash templates or Flash webpage designs look and feel a lot more live and make the site diffrentiate itself from the others largely as a result of animation effects.
Cross Platform Compatibility
Out of all the popular web browsers Flash templates are supported on most of them. Basically, almost all of them have the ability to render Flash. The simple plug-in for Flash takes away all the headache of attempting to make a web site behave itself in IE, Firefox, and Google Chrome.
Vector Graphics
Vector images are so well received simply because they look sharp and unaliased regardless of the display resolution you have or how you resize the image. This is for the reason that they are not image files like .jpg or .png, but rather pieces of code which are rendered right in the browser. When coupled with the effectiveness of a flash template, the consistent lines and crisp and clean animation really are a treat to look at.
Video
This is an additional form of media that Flash renders very nicely. Using the plugin, the videos on a webpage can be rendered regardless of the Operating System. Flash videos perform properly on Windows if the user does not have MediaPlayer and on a Mac if they do not have QuickTime.