Many developers don't understand the key differences across different wmode values of the Flash embed object. In most cases wmode="transparent" value is used even when full transparency is not necessary adding extra overhead to rendering of the Flash movie.Here is a list of possible wmode values with explanations of what each value means:wmode="windows" is the default parameter value. In this mode Flash will play in its own window covering up any other HTML elements. This mode provides the fastest animation performance.wmode="opaque" covers up any HTML elements residing behind the Flash object while allowing elements to show on top of Flash.wmode="transparent" allows flash to show elements residing below the transparent sections of the movie. This mode provides the slowest animation performance.Therefore, if your Flash movie doesn't have any transparencies in it and you are using only DHTML layer that goes over the movie, it is best to use wmode="opaque", rather than wmode="transparent" since in transparent mode flash rendering engine is still trying to apply Alpha to the movie therefore slowing down its performance.
