I was putting in some smart bulbs the other day and I saw that the fitting—the one that you're probably familiar with as the standard screw-in bulb fitting—was called "E27". I found a diagram that showed all the different sorts of bulb fittings which told me that the 'E' in E27 stands for Edison (and and number was the diameter of the bulb's base). Hang on, Edison? The guy who invented them? It hasn't changed in 100 years? It turns out that, yes, the basic screw-in bulb design hasn't really changed since Edison first patented it in the 1880s. It is now an IEC standard, but in the same way that the definition of the metre is now based on the speed of light in a vacuum. This smart LED bulb full of cool technology that means it can go all sorts of colours is fitted in pretty much exactly the same way as a bit of wire that gets very hot from 100+ years ago.