• Rule
• Rule of Thumb
• Law
• Design Heuristic

A principle is a rule which tells whether one solution is better than another one with respect to a certain aspect.

A principle names and explains a certain aspect to consider while assessing a possible solution to a problem. It can be documented using principle descriptions and help talking about solutions.

Principles are a general and universal way to communicate experience. They describe a certain aspect leaving out all the other aspects. So a principle is not a rule that is valid in every case. It's a certain tendency, a rule of thumb or a heuristic that only in combination with other principles gives a complete picture.

• Keep It Simple Stupid (KISS)
• Law Of Demeter (LoD)
• Don't Repeat Yourself (DRY)
• Single Responsibility Principle (SRP)
• ...

• Principle Description
• Principle Catalog
• Principle Language
• Principle Collection

• The term “principle” is often also used to refer to any other rule, heuristic, or philosophy regardless of whether it tells good and bad solutions apart.

Discuss this wiki article and the term on the corresponding talk page.