The plug you use to hook up your headphones to your phone or computer is a piece of living history. Originally used as a telephone switchboard connector, it was invented in 1878, and has been in use ever since.
This invention was created in 1878 making it even older than plug sockets, the first of which was invented in 1883! Making this one of the oldest and yet modern invention of our times. Some inventions come and go, but as for the ¼ audio plugs it seems that it is here to stay.