The Mayflower Compact is best described as an agreement signed by the male settlers aboard the Mayflower to accept whatever form of government they established when they landed at Cape Cod in Massachusetts. According to History.com, it was the first written outline of government in what later became the United States.
The 102 men, women and children aboard the Mayflower included both Pilgrims and non-Puritans such as Miles Standish and John Alden. Originally heading for Virginia, they were blown off course by a storm and ended up in Cape Cod, Massachusetts, which was outside the jurisdiction of existing chartered companies, in November 1620. They named the new land Plymouth after the harbor in England from which they left. Since they were independent, they created their own government under the Mayflower Compact. It was not exactly voluntary, as before male colonists went ashore, they had to sign the agreement. The Mayflower Compact remained valid until 1686 when the Plymouth colony became part of the Dominion of New England. In 1691, this became part of the larger Massachusetts Bay Colony.
The Mayflower Compact was an influence on the Founding Fathers in the drafting of the United States Constitution. The original document was lost, but three copies from the 17th century exist. They differ in wording, spelling, capitalization and punctuation but not in essence.