Step 1: Define affidavit.
An affidavit is a formal legal document, not an oral statement or a judgement.
Step 2: Key elements.
It must be (a) in writing, (b) made on oath or solemn affirmation, and (c) sworn before an authorized officer such as a notary or magistrate.
Step 3: Purpose.
Once sworn, it is submitted to the court as evidence. It is different from a court record or a judgement, both of which are created by the court itself.
\[ \boxed{\text{a written statement made on oath, sworn before an authorized officer and submitted in the court}} \]