What does this mean? : a writen plan for government?

Though it may also be referred to as a charter or code, in most cases a constitution is the written plan of government for a given country. Within a nation's constitution are the fundamental principles and laws designed to govern the people, as well as the methodology and government structure by which the constitution is to be enforced, interpreted and changed.

Delaware, pennsylvania, new jersey, georgia, connecticut, massachusetts bay, maryland, south carolina, new hampshire, virginia, new york, north carolina, and rhode island and providence plantations where the 13 original colonies