
Flash allows the embedding of images, sounds, movies and simple HTML files. Flash's file format is not platform-dependent Flash Players exist on Microsoft Windows, Mac OS, Linux and various other Unix systems.
The Flash file format has been opened by Macromedia, and compatible third-party tools exist. Again, like PostScript, SVG and PDF Flash uses vector graphics they may translate into small file sizes which take less bandwidth to transmit than bitmaps do. In some people's opinions, it is much more difficult to do the same with HTML and CSS. Like PostScript, SVG and PDF, Flash allows exact specification of where the various page elements are, and so it gives the designer a great degree of control over how the user interface looks. Flash circumvents browser controls which block the display of animation on web pages, allowing ads to display animation even when the end user has turned off the capability in the browser.
The Macromedia Flash file format has several advantages over "regular" HTML pages that make it an extremely popular option for ad creation and for some other types of sites.