Transfer machines are highly automated machines that can perform multiple operations on a workpiece in one cycle. These machines are used in mass production for high volume output. Transfer machines can be defined as material processing and material handling machines. This answer can be explained in the following points.

Material Processing Machines:
Transfer machines can perform various material processing operations such as drilling, tapping, milling, boring, reaming, and threading. These operations are performed on the workpiece that is mounted on a fixture or a pallet. The transfer machine moves the workpiece to different stations where each operation is performed by a separate tool. The workpiece is processed simultaneously at each station, resulting in a faster production rate.

Material Handling Machines:
Transfer machines can also be considered as material handling machines as they move the workpiece from one station to another. The transfer machine can be designed with various types of transfer systems such as rotary, linear or shuttle. These systems are used to move the workpiece from one station to another without manual intervention. The transfer machine can also be equipped with an automatic loading and unloading system, which further enhances the automation process.

Component Feeders for Automatic Assembly:
Transfer machines can also be used as component feeders for automatic assembly. The machine can be equipped with a vibratory feeder system that feeds the components to the machine. The transfer machine then assembles the components to form a finished product. This process is highly automated and can increase the production rate significantly.

In conclusion, transfer machines are material processing and material handling machines that can perform multiple operations on a workpiece in one cycle. These machines are highly automated and can be used for mass production.