A more thorough explanation:

The original-writing rule, also known as the best-evidence rule, is an evidentiary rule that requires a party to produce the original writing, recording, or photograph to prove its contents. If the original is unavailable, a duplicate may be used as secondary evidence.

For example, if a party wants to prove the contents of a contract, they must produce the original signed document. If the original is lost or destroyed, a photocopy or other duplicate may be used as secondary evidence.

The purpose of the original-writing rule is to ensure the accuracy and authenticity of evidence presented in court. It prevents parties from relying on hearsay or unreliable copies of documents.