Computer security is a branch of technology known as information security as applied to computers. 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.

Typical approaches to improving computer security (in approximate order of strength) can include the following:

• 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.

For More Information: Computer Security Projects, Experiments & Background Information

Source: Wikipedia (All text is available under the terms of the GNU Free Documentation License)