Web Applications - Refactoring HTML: Improving the Design of Existing Web Applications - page 264

However, what really needs a rethink are sites such as my agent's that use Flash for tasks that HTML can do
perfectly well. In particular, the following common things should never be written as Flash applications:
Navigation
Text content
Noninteractive images
Slide shows
Data entry forms
Invoices
All of these and many, many more can and should be handled by pure XHTML+CSS. On occasion, you might
even throw in a little JavaScript, though I mostly try to avoid that too. There is no excuse for using Flash for any
of these things.
There are a couple of cases where I can see the use of Flash, but it's not strictly necessary. These are sound and
video. For pure sound, you're better off doing a podcast as an MP3 file. Users are unlikely to sit in front of their
computers in their cubicles and listen to a 30-minute show, but they may download it to their iPod and listen to
it on their commute home. However, for background sound on web pages (the Web's equivalent of elevator
music), you may as well use Flash as anything else. Please, please give users a way to turn the sound off if you
do so, though. Nothing makes a user close a window and leave your site faster than hearing the Black Eyed
Peas unexpectedly start blasting "My Humps" in the middle of a crowded office.
For video, Flash actually does seem to be the most reliably cross-platform format. QuickTime doesn't run on
Linux. Most Windows Media files don't play on the Mac without a variety of hard-to-find plug-ins most users
haven't installed. MPEG is covered by a variety of patents, and nobody's sure exactly which ones or how many.
And even if you can sort out the confusing mess that is video codecs, you are then faced with the problem that
the means of embedding videos in a page vary from one browser and platform to the next. It's invalid and
nonstandard.
For the moment, Flash really may be the best choice here, as hard as that is to believe. For the longer term,
though, help is on the way. Several patent-free, open video standards, such as Ogg Theora, are under
development. (They're already supported on Linux, but not yet widely available on more mainstream
platforms.) HTML 5 seems likely to add a video element and maybe even an audio element to go with the
existing img element. However, for the time being, using Flash for video and audio is not out of the question.
Finally, there are what I consider to be the truly evil uses to which unscrupulous webmasters have put Flash. In
particular:
Animated ads
User tracking