Do you avoid using Flash/Silverlight?
  v2.0 Posted at 13/12/2014 6:22 AM by Tiago Araujo

Public Websites done completely with Flash or Silverlight can be very eye-catching and used in the right spots can achieve way more than you can ever achieve with HTML. But beware because:

  • It does not work on an iPhone or iPad
  • Flash/Silverlight can be slow loading, especially if the visitor is not using a fast Internet connection. If your website doesn't load within 5 seconds, they're gone. (There are techniques to overcome this)
  • It is bad for search engine rankings as there is no content for search engine spiders to crawl through. (There are techniques to overcome this)
  • Navigation via the back button (and Browser History). (There are techniques to overcome this)
  • Accessibility
  • Often seen with busy designs that turn off or distract visitors. Look at the biggest ecommerce sites and you notice that none of them are Flash websites
  • In many cases it unnecessarily creates page bloat
  • You can *almost* get the same effects and functionality using jQuery, but faster and lighter
  • You get an inconsistent UI if you use it for controls such as text boxes
  • Flash and Silverlight do not support CSS, so you need to follow unfamilar concepts for re-skinning

Finally, and saddest of all, when Flash/Silverlight is used, it is normally ​over used.

Footnote #1: It is clear that Flash has been quite successful in the past - the penetration of its run time is 99% on PCs, however because of the fact iPhone and iPad dont run it and the growth of HTML 5, Flash is now considered an old technology. 

Footnote #2: The development of Silverlight has been discontinued as ​of 2012 due to the poor acceptance of Silverlight and restrictions Microsoft imposed on its utility. 

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