The
outsole is the layer in direct contact with the ground. Dress shoes often have
leather or resin rubber outsoles; casual or work-oriented shoes have outsoles
made of natural rubber or a synthetic material like polyurethane. The outsole
may comprise a single piece, or may be an assembly of separate pieces, often of
different materials. On some shoes, the heel of the sole has a rubber plate for
durability and traction, while the front is leather for style. Specialized
shoes will often have modifications on this design: athletic or so called
cleated shoes like soccer, rugby, baseball and golf shoes have spikes embedded
in the outsole to improve traction.