Intrusion Countermeasures Electronics (ICE)

Intrusion Countermeasures Electronics (ICE) is a term used in cyberpunk literature to refer to security programs which protect computerized data from being accessed by hackers.

The term was popularized by William Gibson in his short story "Burning Chrome", which also introduced the term cyberspace, and his subsequent novel Neuromancer. According to the Jargon File, as well as Gibson's own acknowledgements, the term ICE was originally coined by Tom Maddox.

When viewed in a cyberspace virtual reality environment, these constructs are often represented by actual walls of ice, stone, or metal. Black ICE refers to ICE that are capable of killing the intruder if deemed necessary or appropriate; some forms of black ICE may be artificially-intelligent.