Foams and foam materials are made from low density elastomers, plastics, and other materials with various porosities. They are used in a variety of architectural, industrial, medical, and consumer applications. There are six basic types of foams and foam materials: open cellular, closed cellular, flexible, rigid, reticular and syntactic. Open cellular foams have interconnected pores or cells and are suitable for filtration applications. Closed cellular foams do not have interconnected pores or cells, but are useful for buoyancy or flotation applications. Flexible foams can bend, flex or absorb impacts without cracking or delaminating. Reticular foams have a very open structure with a matrix consisting of an interconnecting network of thin material strands. Rigid foams feature a matrix with very little or no flexibility. Syntactic foams consist of rigid microspheres or glass micro-balloons held together by a plastic or resin matrix.