Although many people see welding as a specialized skill that is well beyond the scope of an enthusiastic ‘do-it-yourselfer’ advances in technology mean that it is a skill that can be picked up with a little practice by anyone with a small amount of technical competence.
There are many different types of welding, however by far the most popular type for non-professionals is Arc welding. With standard arc welding there are two large metal alligator clips. One connects to a part of the metal work-piece you are welding and the other holds a thin welding rod. As soon as the rod touches the work-piece the electrical circuit is completed and the large current causes massive heat at the point of contact which fuses the steel core of the welding rod to the work-piece, which cools quickly to form a solid bond. Flux surrounding the steel core vaporizes, which forms and inert gas which protects the weld from atmospheric elements which could weaken it.
Two other common types of arc welding, which are more advanced, are MIG (metal inert gas) and TIG (tungsten inert gas) welding. TIG welding is often used for welding steel and aluminum and uses welding rods. MIG welding uses a spool of welding wire which allows longer continuous joints to the welded. In both MIG and TIG welding an inert gas is blown onto the initial weld to protect it instead of using gas flux.