Temperature-sensitive paper, also called thermal paper, is coated with chemicals that darken when heated by a print head. Thermal printers use it instead of liquid ink, which makes them fast, quiet, and common for receipts, shipping labels, tickets, and other short-lived records.
In cyber security, this paper matters because the printed output is often trusted as an operational record. If a system relies on thermal paper for audit trails or proofs of transaction, attackers may try to exploit its physical weaknesses: heat, sunlight, friction, or chemicals can fade or alter the text over time. Defenders reduce risk by storing outputs properly, preserving digital copies, and treating thermal printouts as one layer of evidence rather than a perfect source of truth.