This summary is not the rule. The rule text controls.
If you want to prove what a document, recording, or photo says, you generally need to bring the actual original to court. You can't just describe it or tell the judge what it said. This is often called the "best evidence rule."
There are exceptions to this, which other rules or laws spell out. For example, sometimes a copy is good enough if the original was lost, destroyed, or is hard to get. But as a general rule, if the content of a writing, recording, or photo matters to your case, you should plan on producing the real thing rather than just talking about it or showing a summary.
This rule exists because the exact words or images in a document can matter a lot. Small differences in wording can change the meaning of a contract, a letter, or a recording. Requiring the original helps make sure everyone is looking at the same accurate information, instead of relying on someone's memory or a possibly inaccurate copy.
