Basically, computer security is a branch of technology known as information security as applied to computers. Information security means protecting information and information systems from unauthorized access, use, disclosure, disruption, modification, or destruction. The objective of computer security varies and can include protection of information from theft or corruption, or the preservation of availability, as defined in the security policy.
Technological and managerial procedures applied to computer systems to ensure the availability, integrity and confidentiality of information managed by the computer system. Computer security also imposes requirements on computers that are different from most system requirements because they often take the form of constraints on what computers are not supposed to do. Here are some typical approaches to improving computer security:
- Physically limit access to computers to only those who will not compromise security.
- Hardware mechanisms that impose rules on computer programs, thus avoiding depending on computer programs for computer security.
- Operating system mechanisms that impose rules on programs to avoid trusting computer programs.
- Programming strategies to make computer programs dependable and resist subversion.