Where computer security is all about keeping an intruder out of a computer system, application security is all about preventing a user from performing unauthorized interactions with programs and services running on the computer system.
This is accomplished by implementing authentication, authorization, and auditing. Here, authentication verifies that the user is who he or she claims to be, authorization restricts the user’s actions, and auditing logs all interactions the user has with the system. Keeping applications free from vulnerabilities by detection and patching is also a form of application security.
