Process architecture is the structural design of general process systems and applies to fields such as computers (software, hardware, networks, etc.), business processes (enterprise architecture, policy and procedures, logistics, project management, etc.), and any other process system of varying degrees of complexity.
Processes are defined as having inputs, outputs and the energy required to transform inputs to outputs. Use of energy during transformation also implies a passage of time: a process takes real time to do its thing. A process also requires space for input / output objects and transforming objects to exist: a process uses real space.
A process system is a specialized system of processes. Processes are comprised of other processes. Complex processes are made up of several processes that are in turn made up of several processes. This results in an overall structural hierarchy of abstraction. If the process system is studied hierarchically, it is easier to understand and manage; therefore, process architecture requires the ability to consider process systems hierarchically.