What does the pharse full of faith and credit mean in article iv of the Constitution?

The phrase "full faith and credit" in Article IV of the U.S. Constitution refers to the obligation of states to respect and recognize the public acts, records, and judicial proceedings of other states. This principle ensures that legal decisions and documents, such as marriage licenses and court judgments, are honored across state lines, promoting unity and cooperation among states. It helps maintain legal consistency and stability within the federal system.