Short answers, pulled from the story.
The Amiga 1000, the first model, was announced and offered for sale in 1985. Production problems delayed wide availability; machines only arrived in quantity in mid-November 1985, and 35,000 units were sold by the end of that year.
Jay Miner led the hardware design, working alongside RJ Mical and Dale Luck. Miner had previously designed the graphics and sound chip for the Atari Video Computer System and left Atari after management refused to develop a Motorola 68000-based system.
Estimates vary slightly by source. Amiga Format reported 4,850,000 units in 1993, The Wall Street Journal cited approximately 5,000,000 in 1995, and an independent investigation by YouTuber Stuart Brown estimated 4,910,000 over the platform's lifetime.
The Amiga used custom coprocessor chips to handle graphics, audio, and direct memory access independently of the main CPU. This gave it capabilities like preemptive multitasking in 256 KB of RAM, four PCM audio channels as standard hardware, and a genlock feature that let it overlay computer graphics onto live video signals.
Season one and part of season two of Babylon 5 were rendered in LightWave 3D on Amigas. SeaQuest DSV and Max Headroom also used Amiga systems for special effects. The NewTek Video Toaster, released in 1990, turned the Amiga into an affordable video production platform used in professional television environments.
Commodore struggled as IBM PC compatibles gained 256-color VGA graphics in 1987 and the fourth generation of video game consoles eroded the home market. Commodore shut its Amiga division on the 26th of April, 1994, and filed for bankruptcy three days later. The brand passed through Escom, Gateway 2000, and Amiga, Inc. before the intellectual property was sold to Amiga Corporation in 2019.