Final answer:
True. Welding is indeed classified into two groups: fusion welding and pressure welding.
Step-by-step explanation:
True. Welding is indeed classified into two groups: fusion welding and pressure welding.
Fusion welding involves joining the metal materials by melting them together. This can be done with the use of a heat source, such as a flame or an electric arc.
Examples of fusion welding include arc welding, gas welding, and laser welding.
Pressure welding, on the other hand, involves joining metal materials by applying pressure and using an external heat source, but without melting the materials. This method is commonly used for joining plastic materials. An example of pressure welding is ultrasonic welding.