How does a copy of a document differ from the original?

An original is the document issued and signed by an authorised body; a copy is a reproduction with no evidential force of its own. It gains that force only once it is certified as conforming to the original. In official matters neither is usually enough: you need an odpis, wypis or duplikat from the institution that keeps the document.

Six terms that are not synonyms

Term	What it is	Who issues it
Original	the initial, signed document	the issuer of the document
Copy, photocopy, scan	a reproduction with no evidential force	anyone
Certified copy	a copy with official confirmation of conformity	a notary, the authority handling the case, and in proceedings also a representative who is an advocate or legal counsel
Odpis	the full content issued from a register	the civil registry office, the land register court
Wypis	a document with the force of an original, issued from a notarial deed	the notary office
Duplikat	a reissued document with the force of an original	a school, a university, the issuer of the certificate

In everyday speech all of it is a copy. “I need a copy of a birth certificate” almost always means an odpis from the civil registry office, and “a copy of a notarial deed” means a wypis from the notary office.

When a plain copy is enough

In everyday situations a copy or a scan is perfectly sufficient: providing details for an agreement, reporting an insurance claim, verifying information with an employer, making a booking, completing an internal company form. Nobody is conducting proceedings here in which the document would serve as evidence.

When you need a document from the institution

An office, a court, a notary and a bank performing formal acts will expect a document issued by the body that keeps it, or a certified copy. A copy you made yourself will not replace an odpis, because it does not confirm that the content was left unchanged.

So why keep scans at all

A scan does not replace an original, but it radically shortens the path to restoring one. To order a wypis of a notarial deed you need to know which notary office drew it up, when, and under which repertory number. Those details are on the scan, which takes a minute to find rather than a search through boxes left by your parents.

Example

After a fire in her flat, Ewa has no document on paper. What she does have are scans in an encrypted safe. Using them she orders odpisy of civil status records online, calls the notary office named on the scan of the deed for a wypis, and applies to her school for a duplikat of her certificate. The scans were not evidence in any of those matters. They were the address to apply to.