The Twilight of Flash
Adobe Flash is a multimedia and software platform for authoring animation, games and Rich Internet Applications that can be viewed and played in Adobe Flash Player. Flash has commonly been used on web pages to add streamed video or audio players, interactive media content, and advertisements. Through manipulation of vector and raster graphics, Flash is used to animate text, drawings, and still images.
Perhaps most importantly, Flash is not compatible with the iPhone or iPad. Steve Jobs was reported to dislike Flash and Apple never used it on its devices, which is arguably one of the major reasons users have shifted to different technology. In 2011, Adobe stopped producing Flash for mobile platforms. Mobile devices use HTML5 instead.
HTML5 can be used as audio and video streaming alternative to Flash. Like Flash, it includes features for playing audio and video within websites and both can use integrated vector graphics. Unlike Flash, all web browsers support HTML to some degree. However, HTML5 is immature and cannot yet compete with Flash for advanced uses like gaming. Hence, at least on the upper end, Flash is likely to be around for quite some time. No existing or proposed technology can equal Flash for high level animation and interaction.
Another major issue with Flash is that if you do not have the same version of Flash as the site uses or do not have a Flash plug-in at all, the program does not work at all - there is essentially a blank in the screen. This all or nothing problem is unpopular with users.
In addition, Flash cannot be used by disabled persons who cannot use a mouse to navigate the web. The Americans with Disabilities Act extended its requirements to the internet in 2000 and many sites cannot or will not use Flash because it does not meet the ADA's requirements.
Technology is ever-changing and growing. Five years ago, Flash was virtually the only option for animation, audio, and visual. Make no mistake - it is still used by a majority of the most-visited websites and is in no way obsolete. However, consumer demand for open technology and for technology that works across all platforms has lead a rise in popularity of alternate programs.