Cyber security is the practice of defending computers, networks, and data from malicious electronic attacks. It is often contrasted with physical security, which is the more traditional security practice aimed at controlling access to buildings and other objects in the real world. Although there are plenty of high-tech physical security techniques, and sometimes physical and cyber security are joined together in the org chart under the same executive, cyber security focuses on protecting assets from malicious logins and code, not burglaries.
Link: What is cyber security? Types, careers, salary and certification
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