Storage media is the physical material or device that holds digital data, such as hard drives, SSDs, USB flash drives, memory cards, and magnetic tape. In cyber security, it matters because data does not disappear when a computer is turned off: it can persist on disks, backups, and removable devices, where it may be stolen, copied, recovered, or tampered with.
Attackers often target storage media to exfiltrate files, plant malware on removable drives, or recover sensitive information from discarded hardware. Defenders use full-disk encryption, access controls, endpoint device policies, secure backups, and verified wiping or destruction to reduce risk. In investigations, storage media is also treated carefully because it can contain evidence; forensic teams use write blockers and controlled imaging to avoid changing the original data.