An affidavit is a written statement that you swear to be true before an authorised professional, generally a notary public or solicitor.
Affidavits are used in legal proceedings and usually accompany a witness statement. By presenting information in an affidavit, you make it legally significant so it can be used as evidence.
You will have to sign the document and swear that the contents are accurate to the best of your knowledge. It’s crucial to ensure there is no false information in the statement.