The origins of the steam engine: An essay with interactive animated diagrams (blog.rootsofprogress.org)Steam power did not begin with the steam engine. Long before seventeenth-century scientists discovered the true nature of vacuums and atmospheric pressure, steam- and heat-using devices were being developed. Here we’ll explore the long, little-known story of how the steam engine evolved. And have fun playing with the ancient devices.
History of email (Wikipedia)The history of email entails an evolving set of technologies and standards that culminated in the email systems in use today.