||A new Hardware Specification Language (HSL) called HOP is presented. HOP stands for Hardware viewed as Objects and Processes. It can be used for specifying the structure, behavior, and timing of digital systems. HOP was designed for several reasons. It integrates well-tested ideas from past work that was based on an abstract data type view of hardware systems into a new, simple, and deterministic process model that we have invented. Our process model is inspired by the works of Mil82, Mil83, and Hoa85. Secondly it is believed that not only should an HSL be founded in mathematical principles, but it also ought to be simple, intuitive to use, and address practical issues, especially if practicing VLSI designers are to be encouraged to use them. HOP was designed to meet the following design objectives: 1) Be capable of modeling large architectures as well as simple MOS digital circuits; 2) support the writing of a priori as well as a posteriori specifications; 3) possess a simple and rigorous semantics; 4) support static analysis techniques and design verification; 5) match digital designer's intuitions closely; 6) be demonstrably efficient in handling many important practical issues; 7) act as a common repository of related information falling in various domains (functional behavior, timing, geometry, and user documentation to a name a few) thereby helping in designer and tool integration; 8) support design automation as well as manual design.