A welding machine is a device that joins metal components by generating high heat to melt and fuse the materials together. It operates using various welding techniques, including arc welding, MIG (Metal Inert Gas), TIG (Tungsten Inert Gas), and spot welding, depending on the application and the type of material. Welding machines are commonly used in construction, automotive, aerospace, and industrial fabrication, as they provide strong and durable metal joints.