ISHIKAWA
A Cause-and-effect (Ishikawa) diagram is a problem solving analysis tool that provides a systematic way of looking at effects, as well as the causes that create or contribute to those effects.
The diagram was developed by Kaoru Ishikawa who pioneered quality management processes and became one of the founding fathers of modern problem solving.
It is a graphical representation of the trail leading to the root cause of a problem and is sometimes referred to as an Fishbone Diagram because of its shape.
You can use this diagram…
To analyse and find the root cause of a problem
When there are many possible causes for the problem
If the traditional way of approaching the problem (trial and error, trying all possible causes, and so on) is very time consuming.