https://www.siliconvalley.com/2019/10/04/magid-microsoft-hardware-future-may-hinge-on-hinges/

The website Thomasnet.com says that “Hinges have been found in ancient societies in Africa, Asia, Europe and elsewhere,” dating back 5,500 years.

Historically, they were used to open doors, but as Harry McCracken wrote in a 2012 Technologizer post, in April, 1982, Grid Systems announced a portable computer “with a screen on one half of the interior, a keyboard on the other and a hinge in the middle. It was, in other words, the first computer with a clamshell case–or, to use a more common term, the first laptop.”