Computer security, also known as cybersecurity or IT security, is the protection of information systems from theft or damage to the hardware, the software, and to the information on them, as well as from disruption or misdirection of the services they provide.

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 thembeing tricked into deviating from secure procedures.

The field is of growing importance due to the increasing reliance on computer systems in most societies and the growth of "smart" devices, including smartphones, televisions and tiny devices as part of the Internet of Things – and of the Internet and wireless network such as Bluetooth and Wi-Fi.

Some organizations are turning to big data platforms, such as Apache Hadoop, to extend data accessibility andmachine learning to detect advanced persistent threats.