A more thorough explanation:

Refreshing recollection is when a witness's memory is improved by looking at a document that describes the events they are testifying about. This document is not used as evidence, but only as a way to help the witness remember what happened.

During a trial, a witness is asked about an incident they witnessed. The witness is having trouble remembering the details. The lawyer shows the witness a written statement they made shortly after the incident. After reading the statement, the witness is able to remember more clearly what happened and can testify more accurately.

This example illustrates how refreshing recollection works. The document is used to help the witness remember what happened, but it is not used as evidence itself.