A Cause and Effect Diagram (aka Ishikawa, Fishbone) showing possible causes (process inputs) for a given effect (process outputs).
The process mapping is a tool that graphically shows the inputs, actions & outputs of a process in a clear, step-by-step map of the process.
A SIPOC (Supplier, Input, Process, Output, and Customer) is a high-level process mapping tool to help visualize a process and its influences.
Benchmarking is the process of comparing current methods against world class performers to create the best possible performance.