ITA key terms

The main chip that executes program instructions by fetching, decoding, and running them. It performs arithmetic, logic, and control operations for the whole computer system.

Volatile working memory that holds programs and data currently in use. Its contents are lost when power is removed, and insufficient capacity causes slowdowns through swapping.

Non-volatile storage using flash memory chips with no moving parts. It offers faster access and greater shock resistance than a spinning hard disk, though cost per gigabyte is higher.

The main circuit board that connects the processor, memory, storage, and expansion cards. It carries the chipset, buses, and firmware that let components communicate.

Firmware stored on the motherboard that initializes hardware at startup and hands control to the operating system. Modern systems often use its successor, UEFI, with added features.

A widely used standard connector and protocol for attaching peripherals such as keyboards, drives, and printers. It supports hot-swapping and supplies power to connected devices.

Any hardware attached to a computer to add capability, such as a monitor, printer, or scanner. Peripherals rely on drivers and interfaces to exchange data with the host system.

Software that lets the operating system communicate with a specific piece of hardware. It translates generic commands into instructions the device's controller understands.

System software that manages hardware resources, runs applications, and provides services such as file systems and user interfaces. Examples include Windows, Linux, and macOS.

A technique where the operating system uses disk space to extend physical memory. Less-used pages move to disk, letting programs exceed installed RAM at a performance cost.

The sequence from power-on to a usable system: firmware self-tests, locates a boot device, and loads the operating system kernel. Failures here often indicate disk or firmware problems.

A legal agreement defining how software may be installed, used, copied, and distributed. Types include proprietary, open source, and subscription models, each with different obligations.

A numeric label assigned to a device on a network so data can be routed to it. IPv4 uses 32-bit addresses; IPv6 uses 128-bit addresses to overcome address exhaustion.

A value that separates the network portion of an IP address from the host portion. It lets devices decide whether a destination is local or must be reached through a router.

The router address a device sends traffic to when the destination lies outside its local subnet. A wrong or missing gateway blocks access to remote networks and the internet.

A hierarchical service that translates human-readable names into IP addresses. DNS failures typically appear as name-resolution errors while direct IP connections still work.

A protocol that automatically assigns IP addresses, subnet masks, gateways, and DNS servers to clients. It reduces manual configuration errors on larger networks.

An encrypted tunnel that carries traffic between a remote device and a private network over the internet. It protects data in transit and can extend internal access to off-site users.

A security control that permits or blocks network traffic according to defined rules. It can be host-based or network-based and filters by address, port, or application.

The process of transforming readable data into ciphertext so only authorized parties can recover it. It protects data at rest and in transit and depends on secure key management.

Requiring two or more independent evidence types, such as a password plus a one-time code, before granting access. It reduces risk from stolen or guessed passwords.

A social-engineering attack that impersonates a trusted party to trick users into revealing credentials or running malicious content. Awareness training and link inspection are key defenses.

Any software designed to harm, disrupt, or gain unauthorized access to a system, including viruses, worms, ransomware, and spyware. Antivirus tools and patching reduce exposure.

Granting users and processes only the access needed to perform their tasks, and no more. It limits the damage a compromised account or flawed program can cause.

A structured approach to resolving faults: gather information, identify the cause, test a fix, verify results, and document the outcome. Consistency prevents repeated or random changes.

A record of system, application, and security activity kept by the operating system. Logs help diagnose faults and reveal patterns such as repeated login failures or driver errors.

The process of tracing a problem past its symptoms to the underlying cause so it can be permanently corrected. It contrasts with quick fixes that let the fault recur.

Planning and applying software updates that fix bugs and close security gaps. A defined cycle of testing, deployment, and verification keeps systems current without introducing instability.

A column or set of columns that uniquely identifies each row in a table. It cannot contain duplicate or null values and enforces entity integrity.

A column that references the primary key of another table, creating a link between them. It enforces referential integrity by preventing orphaned records.

A data store organized into tables of rows and columns, related through shared key values. Queries use SQL to select, join, and modify records.

The standard language for creating, querying, and modifying data in relational databases. Statements include SELECT for retrieval and INSERT, UPDATE, and DELETE for changes.

A copy of database data and logs kept so it can be restored after loss or corruption. Restore testing is essential because an untested backup may not be usable.

HTTP carried over an encrypted TLS connection, protecting data exchanged between browser and server. It authenticates the server with a certificate and prevents tampering in transit.

A defined set of rules and endpoints that lets one program request data or actions from another. APIs commonly exchange structured data such as JSON over HTTPS.

A delivery model where a provider hosts an application and customers access it over the internet, usually by subscription. Maintenance and patching become the provider's responsibility.

A documented commitment between a service provider and a customer covering scope, availability targets, and response times. It defines measurable expectations and consequences for shortfalls.

The practice of restoring normal service as quickly as possible after an unplanned disruption. It prioritizes speed of recovery and communication over finding the underlying cause.

A controlled process for reviewing, approving, and recording modifications to IT systems. It reduces the risk that updates cause outages and keeps an auditable history.

The maximum acceptable amount of data loss measured in time before a disruption. It guides backup frequency, since data created after the last backup would be lost.