Axiom is  a general purpose Computer Algebra system. It is useful for research and development of mathematical algorithms. It defines a strongly typed, mathematically correct type hierarchy. It has a programming language and a built-in compiler.
Polybutylene is simply a type of plumbing material that was manufactured between the late 70's and early 90's. It is thought that it was installed in over 6 million homes during that time period.
The final type of plastic plumbing pipe is PolyPipeÂ®, a thick black pipe used to transport highly pressurized water, usually to and from the home. It is used almost exclusively outdoors, and is usually buried underground to prevent freezing.