Explain Welding? Easy and hard so lets start with the easy. Welding is simply the melting of two adjacent metalic surfaces together such that the molecular structure of each piece intertwines as if it were one contiguous piece of metal. Well that is accoring to Poindexter, at a macro level it is simply melting two bits of metal together. On a more complex level Welding then breaks into categories based on the type of process, be it TIG, Mig, Arc or Plasma welding. They all do the same as mentioned in the foreword but do it differently so call us on 1300 881 991 to help you find the machine most suited to your needs.