Adobe's Flash, like Microsoft's Active-X, once filled a critical gap in web technologies. Once that gap no longer needed filling, though, Flash went from being progressive to regressive. Now, finally, Adobe is letting Flash wind down.
From Adobe, on the long, slow wind-down:
Given this progress, and in collaboration with several of our technology partners – including Apple, Facebook, Google, Microsoft and Mozilla – Adobe is planning to end-of-life Flash. Specifically, we will stop updating and distributing the Flash Player at the end of 2020 and encourage content creators to migrate any existing Flash content to these new open formats.
From Apple, who saw this most obvious of futures earlier than any of its competitors or critics, via its open source WebKit project:
Adobe has announced it will stop distributing and updating Flash Player at the end of 2020 and is encouraging web developers to migrate any existing Flash content to open standards. Apple is working with Adobe, industry partners, and developers to complete this transition.
Apple users have been experiencing the web without Flash for some time. iPhone, iPad, and iPod touch never supported Flash. For the Mac, the transition from Flash began in 2010 when Flash was no longer pre-installed. Today, if users install Flash, it remains off by default. Safari requires explicit approval on each website before running the Flash plugin.
That permission will also time out after a month if you don't continue visiting the site. Given how exploitable Flash has proven as an attack vector for malware over the last few years, and how unnecessary it's become for the modern web, I'd recommend simply leaving it uninstalled.