Computer security is a segment of technology that deals with keeping computers, their software, and the information (data) they process, safe from harm or theft. Four procedures or mechanisms that typically comprise the security process are:
- 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.
Computer security often begins with a firewall (a hardware or software device that controls access to the computer through any network connections) and involves the use of passwords, logs, software checks and barriers, and other software (program) and hardware (device) functions.