Flows is the shorthand term I am using to describe, well, diagrams that are not site maps. Included here is a selection that includes user flows, system flows, service design flows, process flows, and the like. I am also including use cases as a type of flow because I most often uses diagrams to depict use cases. I have also made a lot of non-diagram use cases for UAT, QA, and business requirements, but those are much less typical of my work.
Flows help to document and communicate processes and logic as well as the pitfalls and desired results of processes and logic. Often I will start by documenting a legacy process to understand the process and to analyze what is and is not working. From there I can quickly identify areas needed improvement and often identify issues others had not previously known about.