WHAT IS COMPUTER SECURITY?

Computer security involves protecting computers and networks from malware, hackers and other threats while maintaining privacy on the Internet and on physical systems and networks.

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Both physical and digital factors are considered, because either can cause a system's integrity to be compromised. Major areas covered include physical access security, operating system security, data integrity and protection, and network access and intrusion. The goal of computer security is to lessen these risks as much as possible and to use countermeasures to fix security issues as quickly as possible. 

Physical access is one of the most critical factors in securing computer systems and networks. Even if one takes measures to encrypt data and block network access, these will be pointless if someone steals the physical system or gains direct access to it. Physical security involves securing the building containing the computer by using special doors, identification processes and security cameras. It also involves training employees not to give their passwords to strangers and to recognize social engineering techniques.

Operating system security is another important factor of computer security. If an attacker gains control of a person's computer, he or she can control the victim's operating system, steal data and destroy important information. Security holes are found in most common operating systems, so vendors periodically release patches users can install to better secure their systems. Viruses and spyware also present a risk to many operating systems, so virus protection software is needed to prevent data loss and unauthorized access. If a computer is in an area with a lot of people around it, users should also use complex passwords to prevent unauthorized users from making changes or reading sensitive data on their computers.

Computer hard drives, optical media and flash storage often contain personal information, so computer security emphasizes protecting these items with encryption that improves the security of data by making it unreadable to unauthorized parties. Many operating systems have features that can encrypt single files or entire hard drives. Special hardware is available that can encrypt data even when accessed on a different computer.

Securing computer networks is critical to computer security. Hackers who find information on a company's network can use tools to gain access to other computers and servers. A firewall helps to block network access and can be configured to various levels of security. Wireless networks also have encryption features that can protect data and prevent unauthorized network access.


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