Why do light bulbs come in bayonet and s***w versions? Why don't we all switch to bayonet?

Question

Why do light bulbs come in bayonet and s***w versions?

Why don't we all switch to bayonet?

Is the bayonet/s***w thing the same around the world?

Answer 1

The US uses mainly Edison s***w bulbs. The UK has traditionally used bayonet but with snazzier light fittings coming in there has been an influx of Edison s***w (ES) and miniature Edison s***w (MES) fixtures. The main hassle of ES and MES bulbs is that they can stick in the sockets and are a real pain to remove.