Flash Player - 64 Bit Windows10
But beneath the surface, trouble was brewing. Flash was "power-hungry" and riddled with security holes that hackers loved to exploit. In 2010, Steve Jobs famously wrote an open letter, "Thoughts on Flash," refusing to allow it on the iPhone, which signaled the beginning of the end. As newer, safer technologies like matured, the world realized it no longer needed a clunky third-party plugin to watch videos or play games. The Final Chapter
However, if you have a specific, critical need to run legacy Flash content on Windows 10 (64-bit), here are the available options: flash player 64 bit windows10

