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.
What Is a PBX Switchboard? PBX is an acronym for private branch exchange, an in-house telephone switching system used to interconnect both internal and external telephone extensions and networks. Its functions include least-cost routing for external calls, conference calling, call forwarding and call accounting.