In your own words, what is the purpose of a constitution?

Answer in two short sentences (15 word limit). You will have a chance to explain in more detail later.

Example sentence frame:
The purpose of a constitution is

Make it sound like a fifth grader wrote it

The purpose of a constitution is to make rules for a country and protect rights.

A different purpose

The purpose of a constitution is to establish the framework for government and define its powers.