Short answers, pulled from the story.
Jay Miner designed the Amiga computer with the vision to build a computer that could do everything a television studio could do for the price of a home appliance. He led the development of the Television Interface Adaptor at Atari before founding Hi-Toro and later Amiga Corporation to realize this goal.
The Amiga 1000 was released in July 1985 but became widely available in early 1986 due to production problems. By the end of 1986, 120,000 units were reported as having been sold from the machine's launch.
The Amiga custom chipset included the blitter for graphics and the Paula chip for audio which allowed the system to handle graphics and sound independently of the central processing unit. This architecture enabled the system to display up to 4,096 colors simultaneously and generate four channels of sample-based audio.
Commodore shut down the Amiga division on the 26th of April 1994 and filed for bankruptcy three days later. The company had been left without a workable path to creating a next-generation home computer after Jack Tramiel resigned and formed Tramel Technology.
The Amiga machines were most popular in the UK and Germany with about 1.5 million sold in each country. Sales in North America were estimated at 700,000 units which was less popular than in Europe.
AmigaOS 4 is developed by Hyperion Entertainment and runs on PowerPC-based hardware while MorphOS is developed by the MorphOS Team and continues on Apple and other PowerPC-based hardware. AROS is a free and open source operating system that serves as a re-implementation of the AmigaOS 3.1 APIs for Amiga 68k, x86 and ARM hardware.