Sir Humphry Davy did more than just invent electric welding in 1800 when he created electric arcs between two carbon electrodes using batteries. He set a precedent for welding innovation that continues to this day.
The period from the early 1800s to the mid-1900s brought the development of arc welding, various types of resistance welding (spot, seam, projection, flash butt), and gas metal arc (MIG) and gas tungsten arc welding (TIG). Since then, robotic welding has become a staple of several industries, and friction, spin, laser and ultrasonic welding have become mainstream.