The original PowerPoint was first manufactured in the seventeenth century.
The magic lantern was a form of image projector that used bright light to project pictures painted on sheets of glass onto a screen, perhaps a white wall or a sheet. In the days before radio, film, television, social media, and the general availability of books, it was a huge source of entertainment. You could illustrate Bible stories, travel tales, all sorts of phantasmagoria, or simply project images of Death onto people’s windows to scare them into attending church.
As technology developed, the glass gave way to photographic film and the format was standardised in 35mm slides. Slide projectors were popular in all sorts of institutional and educational environments. You could whip through a series of talks on fourteenth-century Italian art, say, with suitable illustrations viewed by many people at once. Year after year.
But why stop at education? Put the snaps of the latest family wedding, holiday or new baby onto slides, and you could treat the whole extended clan to a three-hour audio-visual experience with live commentary.
It’s probably only the poorest Scout troop in the world that is learning its flags and knots from overhead projectors in a draughty hut these days, but slides were once ubiquitous.
Actually, they still are. What you produce in PowerPoint is even to this day called a slideshow. There just aren’t any slidy things involved any more.