This discussion is intended to be technology-neutral. The tasks described here may be performed manually or by computer. At this point our focus is on what (conceptually) needs to be done, not how (physically) it is accomplished. At various stages in the processes, we will examine specific documents, journals, and ledgers as they are encountered. Again, this review is technology-neutral. These documents and files may be physical (hard copy) or digital (computer generated). In the main body of the chapter we examine examples of physical systems.