A more thorough explanation:

An unwritten constitution is a collection of customs, values, and traditions that provide the fundamental law of a state or country that does not have a single written document functioning as a constitution. It is different from a written constitution, which is a formal document that outlines the fundamental principles and laws of a nation or state.

For example, the British Constitution is an unwritten constitution that includes historical documents, statutes, decrees, conventions, traditions, and royal prerogatives. It does not have a single written document that outlines its fundamental principles and laws.

Another example of an unwritten constitution is the implied parts of a written constitution. These are the rights, freedoms, and processes considered to be essential but not explicitly defined in the written document. For instance, the U.S. Constitution does not expressly guarantee a right to privacy, but the Supreme Court has declared that the right exists and is protected.

Overall, an unwritten constitution is a flexible system that can adapt to changing circumstances and societal values. It is based on customs and traditions that have evolved over time and are deeply ingrained in the culture of a nation or state.