Mallets are usually made from rubber or wood, making it great for finishing a product as it won't leave any marks on the surface. Using these softer materials as the striking face it will provide a softer impact compared to steel. They are used in applications where a steel hammer is too hard, for example laying tiles where a force is needed, but a softer strike to ensure the tile doesn't break.

Types of Mallets

Wooden Mallet: Typically used in carpentry to knock wooden pieces together, or to drive dowels or chisels.
Rubber Mallet: Typically used when a softer blow is required. They are typically used to form sheet metal since they do not leave marks and are less likely to dents.
Brass, Copper Mallet: Typically used on machinery to apply force to parts with a reduced risk of damaging them, and to avoid sparks.
Plastic Mallet: Made of nylon, polycarbonate, or Polyethylene. Typically used in leather-work and jewellery applications.

Mallets are used in a variety of applications such as:

Carpentry
Construction
Framing
Geology
Masonry
Mining
Punching
Upholstery
Welding