There are 50 different joining processes. They all have their place.
How many can you name.
I will start the list.
GMAW (MIG)
GTAW (TIG)
SMAW (Stick welding)
Electron Beam welding
FCAW (flux core)
Duel shield /spray transfer
Thermite welding (railroad rails)
Air acetylene welding
Oxy-acetylene welding
Oxy-hydrogen welding
Pressure gas welding
Carbon arc welding
Submerged arc welding (SAW) with powdered flux.
Plasma arc welding
Stud arc welding
Electro slag welding
Spot welding
Seam welding
Percussion welding
High frequency welding (ultra sonic) USW
Projection welding
Resistance butt welding
RSW (resistance spot welding)
Flash butt welding
Solid state welding
Friction stir welding
Laser beam welding
Explosive welding
EDM welding (electrical discharge and machining welding)
EPW (electron pulse welding)
Cold wire TIG
Hot wire TIG
Vacuum furnace brazing (VFB)
PLASTIC WELDING
Hot gas welding
Freehand welding
Speed tip welding
Extrusion welding
Contact welding
Hot plate welding
High frequency welding
Injection welding
Ultrasonic welding (of plastic)
Friction welding
Spin welding
Laser welding
Solvent welding
On a Roadstar Adventure.