Digital evidence preservation is the process of keeping electronic records intact so they can still be used later in an investigation or court case. In cyber security, this matters because logs, messages, files, cloud records, and device data can disappear quickly through retention limits, user deletion, system rotation, or tampering.
In real incidents, preservation helps investigators capture account records, server logs, chat history, screenshots, and metadata before they expire or are overwritten. Defenders use preservation workflows, legal holds, and secure copies to maintain integrity and support chain of custody. Attackers often try to defeat this by deleting traces, wiping devices, or using short-lived accounts, so fast preservation can be the difference between a usable case and lost evidence.