Computer security, also known as cyber security or IT security, is the protection of computer systems from the theft or damage to the hardware, software or the information on them, as well as from disruption or misdirection of the services they provide.
Computer software, or simply software, is that part of a computer system that consists of encoded information or computer instructions, in contrast to the physical hardware from which the system is built.
A computer is a device that can be instructed to carry out an arbitrary set of arithmetic or logical operations automatically.
Security is the degree of resistance to, or protection from, harm.
Introduction to Computer Security - Information Security ... by Dr. Daniel Soper
It includes controlling physical access to the hardware, as well as protecting against harm that may come via network access, data and code injection, and due to malpractice by operators, whether intentional, accidental, or due to them being tricked into deviating from secure procedures.
Code injection is the exploitation of a computer bug that is caused by processing invalid data.
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The field is of growing importance due to the increasing reliance on computer systems and the Internet in most societies, wireless networks such as Bluetooth and Wi-Fi – and the growth of "smart" devices, including smartphones, televisions and tiny devices as part of the Internet of Things.
The Internet of things is the internetworking of physical devices, vehicles, buildings, and other items—embedded with electronics, software, sensors, actuators, and network connectivity that enable these objects to collect and exchange data.
A smartphone is a mobile phone with an advanced mobile operating system which combines features of a personal computer operating system with other features useful for mobile or handheld use.
Wi-Fi or WiFi is a technology that allows electronic devices to connect to a wireless LAN network, mainly using the 2.4 gigahertz UHF and 5 gigahertz SHF ISM radio bands.