Concrete sealer has become an essential part of almost all concrete finishes. It is widely used as a curing agent for new concrete and a protective barrier for existing concrete. It also protects the surface from any chemicals, especially acids, that may be spilled and makes cleanup easy. Any spills can be easily mopped or rinsed away. It prevent hideous oil stains on driveways and garage floors, rust stains from aging patio furniture, grease stains from dripping grills, or those nasty black and green mold stains. There are two basic types of concrete sealers, which includes surface concrete selear and penetrate concrete selear.