The flash player, years ago, was primarily used to enable rich web content, such as video playback, to be placed into web pages when it couldn’t be done using web standards at the time. It also found use for online web browser games.
Many of its uses, such as video playback, were later supplemented by modern web standards (such as HTML5 and it’s video element).
As it has fallen out of common use and is prone to security flaws, adobe has decided its no longer worth maintaining.
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