Spot-welding is a process used in manufacturing to join two pieces of metal together by creating a series of small welds. There are several synonyms for the term spot-welding, including resistance welding, projection welding, and micro-welding. Resistance welding is a broader term that encompasses a range of welding techniques used to join metals without the use of filler materials. Projection welding is a variation of resistance welding that uses raised portions or projections on the metal surface to create a series of tiny welds. Micro-welding, on the other hand, refers to the welding of very small objects or parts, often using a laser or other high-precision tool.