How Did Stephen Hawking Talk and Type Without Physical Control?

Stephen Hawking used a speech-generating device (SGD) or a voice output communication aid to communicate. This device is designed to supplement or replace speech and writing for people who have difficulty communicating in a traditional way. Since 1997, Hawking has been using a computer-based communication system made by Intel Corporation. The entire computer system was replaced every two years to accommodate his gradual loss of muscle control over time. Hawking also wrote a short post titled ‘The Computer,’ briefly discussing the tools that helped him communicate.