Complex sentence: First released in 1996 as FutureSplash Animator, and then re-christened Macromedia Flash upon its acquisition by Macromedia, it was first created to serve as the main authoring environment for the Flash Player--a vector-based platform for the creation of animated and interactive content.
Split into simpler sentences: First released in 1996 as FutureSplash Animator, and then re-christened Macromedia Flash upon its acquisition by Macromedia. It was first created to serve as the main authoring environment for the Adobe Flash platform, a vector-based platform for the creation of animated and interactive content.