A bradawl is a woodworking hand tool with a blade similar to that of a straight screwdriver and a handle made from wood or plastic.
A bradawl is used to make indentations in wood or other materials in order to ease the insertion of a nail or screw. The blade is placed across the fibres of the wood, cutting them when pressure is applied. The bradawl is then twisted through 90 degrees which displaces the fibres creating a hole. This cutting action helps to prevent splitting of the wood along the grain.
Chisholm, Hugh, ed. (1911). Encyclopædia Britannica (11th ed.). Cambridge University Press..