First published in 1983, the Department of Defense Trusted Computer System Evaluation Criteria, DOD5200.28STD known as the Orange Book is the de facto standard for computer security today. The Orange Book, and others in the Rainbow Series, are still the benchmark for systems produced almost two decades later, and Orange Book classifications such as C2 provide a shorthand for the base level security features of modern operating systems.

Website: http://www.dynamoo.com/orange/