A principle stating that a system should be liberal in what it accepts and conservative in what it sends, meaning it should handle user input flexibly while providing clear, consistent output, similar to the principle of fault tolerance.
A design principle that ensures a system continues to function at a reduced level rather than completely failing when some part of it goes wrong.
The capability of a system to continue operating properly in the event of the failure of some of its components, ensuring that user experience is not significantly affected by errors or issues, similar to Postel's Law.