Computer systems in the context of Computation

Computer security (also cybersecurity, digital security, or information technology (IT) security) is a subdiscipline within the field of information security. It focuses on protecting computer software, systems, and networks from threats that can lead to unauthorized information disclosure, theft or damage to hardware, software, or data, as well as from the disruption or misdirection of the services they provide.

The growing significance of computer insecurity reflects the increasing dependence on computer systems, the Internet, and evolving wireless network standards. This reliance has expanded with the proliferation of smart devices, including smartphones, televisions, and other components of the Internet of things (IoT).

An IT administrator, system administrator, sysadmin, or admin is a person who is responsible for the upkeep, configuration, and reliable operation of computer systems, especially multi-user computers, such as servers. The system administrator seeks to ensure that the uptime, performance, resources, and security of the computers they manage meet the needs of the users, without exceeding a set budget when doing so.

To meet these needs, a system administrator may acquire, install, or upgrade computer components and software; provide routine automation; maintain security policies; troubleshoot; train or supervise staff; or offer technical support for projects.

Cyberwarfare is the use of cyber attacks against an enemy state, causing comparable harm to actual warfare and/or disrupting vital computer systems. Some intended outcomes could be espionage, sabotage, propaganda, manipulation or economic warfare.

There is significant debate among experts regarding the definition of cyberwarfare, and even if such a thing exists. One view is that the term is a misnomer since no cyber attacks to date could be described as a war. An alternative view is that it is a suitable label for cyber attacks which cause physical damage to people and objects in the real world.

A name–value pair, also known as an attribute–value pair, key–value pair, or field–value pair, is a fundamental data representation in computer systems and applications. Designers often desire an open-ended data structure that allows for future extension without modifying existing code or data. In such situations, all or part of the data model may be expressed as a collection of 2-tuples in the form <attribute name, value> with each element being an attribute–value pair. Depending on the particular application and the implementation chosen by programmers, attribute names may or may not be unique.

Common examples include JSON objects such as database records where a column maps to a stored value (e.g., username → johndoe), HTTP headers like Content-Type: text/html, and configuration files with settings expressed as settingType=1.

Code injection is a computer security exploit where a program fails to correctly process external data, such as user input, causing it to interpret the data as executable commands. An attacker using this method "injects" code into the program while it is running. Successful exploitation of a code injection vulnerability can result in data breaches, access to restricted or critical computer systems, and the spread of malware.

Code injection vulnerabilities occur when an application sends untrusted data to an interpreter, which then executes the injected text as code. Injection flaws are often found in services like Structured Query Language (SQL) databases, Extensible Markup Language (XML) parsers, operating system commands, Simple Mail Transfer Protocol (SMTP) headers, and other program arguments. Injection flaws can be identified through source code examination, Static analysis, or dynamic testing methods such as fuzzing.