Operating System Glossary

As a tech-savvy individual, it is crucial to possess a fundamental familiarity with the lexicon and principles pertinent to operating systems.

From startup directories and system invocations to virtual memory and trojans, there are many technical terms that can be perplexing for those inexperienced in the realm of computing.

In this blog post, we will provide a glossary of prevalent operating system terminology to aid in your comprehension of how your computer operates and resolve any potential issues that may arise.

Regardless of your level of expertise, having a solid foundation of knowledge about operating systems is indispensable for optimizing your computer’s performance and ensuring its optimal functioning.

Terms A-Z

API (Application Programming Interface): A comprehensive set of protocols and tools for constructing sophisticated software applications.

Abstraction: A programming concept that involves exposing only the essential characteristics and behaviors of an object, while concealing its intricate implementation details.

Adware: Irksome software that displays unwanted advertisements on a computer.

Antivirus: Indispensable software that detects and removes malevolent malware from a computer.

Application sandbox: A secure, isolated environment that prevents an application from accessing sensitive data or making unauthorized modifications to the system.

“OS sandboxing technology runs below the endpoint device’s operating system on bare-metal hardware. It splits each device into multiple, local virtual machines, each with its own operating system. Everything end-users do happens in different operating systems, which run side-by-side with full separation.” Source

BIOS (Basic Input/Output System): Low-level firmware that controls the boot process of a computer and provides basic input/output functions.

Boot: The crucial process of starting up a computer.

Bootloader: Essential software that loads the operating system kernel during the boot process.

Cache: A small, fast area of memory that stores frequently accessed data to improve performance.

Cloud computing: The innovative delivery of computing resources over the internet, allowing users to access data and applications remotely.

Cluster: A group of computers that work together seamlessly to perform a task or process.

Command line interface: An interface that allows users to interact with the operating system using text-based commands, providing a powerful and efficient way to communicate with the system.

“A command line interface (CLI) enables users to type commands in a terminal or console window to interact with an operating system. Users respond to a visual prompt by typing a command on a specified line, and receive a response back from the system. Users type a command or series of commands for each task they want to perform.” Source

Compiler flag: An important option that is passed to a compiler to specify how it should process the source code.

Compiler: A program that translates source code into machine code that can be executed by a computer, enabling the creation of executable programs.

Concurrency: The ability of an operating system or program to execute multiple tasks or processes concurrently, improving efficiency and performance.

DLL (Dynamic Link Library): A useful library of functions that can be loaded and used by multiple programs, providing a convenient way to share code.

Daemon: A useful background process that performs tasks or services for other programs, running unobtrusively in the background.

Deadlock: A predicament in which two or more processes are impeded and unable to proceed, causing a system to become unresponsive.

Debugger: A tool that assists in the identification and correction of errors in a program by enabling the developer to inspect the state of the program as it executes.

Desktop: The main screen or workspace of a computer, where users can place icons, files, and other objects.

Device driver: A program that enables a computer to communicate with a specific hardware device.

Directory: A repository on a computer where files and other directories can be stored.

Domain controller: A server that oversees the security and policies of a domain.

Domain name system (DNS): A complex system that translates domain names (such as www.example.com) into IP addresses, allowing computers to communicate with each other flawlessly.

Domain: A diverse collection of computers that share a common name and are administered together harmoniously.

Dynamic host configuration protocol (DHCP): A protocol that automatically and proficiently assigns IP addresses to devices on a network.

“Every device on a TCP/IP-based network must have a unique unicast IP address to access the network and its resources. Without DHCP, IP addresses for new computers or computers that are moved from one subnet to another must be configured manually; IP addresses for computers that are removed from the network must be manually reclaimed” Source

Encapsulation: A programming concept that involves bundling data and functionality together in a cohesive unit, or object.

Encryption: The process of encoding data to make it unreadable and secure from unauthorized users.

Event-driven programming: A programming paradigm that is based on the use of events, such as user input or system notifications, to trigger the execution of code in a reactive manner.

File compression: The process of reducing the size of a file by eliminating unnecessary or redundant data.

File extension: A unique set of letters that follows the name of a file and indicates the type of file it is.

File index: A sophisticated data structure that stores the locations of files on a computer, allowing them to be swiftly and effortlessly retrieved.

File permission: A comprehensive set of rules that determine which users or groups can access a file or directory.

File system check: A thorough diagnostic process that verifies the structural stability of a file system and promptly resolves any flaws.

File system driver: A sophisticated software program that facilitates the smooth communication between the operating system and the file system, enabling the seamless exchange of data.

File system mount: The process of attaching a file system to a directory in the operating system, making it readily accessible to the user.

File system unmount: The process of detaching a file system from a directory in the operating system, rendering it completely inaccessible to the user.

File system: A sophisticated system of organization and storage of files on a computer, allowing for quick and efficient retrieval and manipulation.

File: A digital record containing important information that is stored on a computer.

Firewall: A robust network security system that controls incoming and outgoing traffic based on predetermined security rules, safeguarding the system from malicious attacks. 

Related: Firewall & Security Management

Firmware: Low-level software that is permanently stored in a hardware device and controls its fundamental functions.

Functional programming: A programming paradigm that is based on the use of functions to manipulate data, rather than using state and mutable data.

“Functional programming (also called FP) is a way of thinking about software construction by creating pure functions. It avoid concepts of shared state, mutable data observed in Object Oriented Programming.” Source

GUI (Graphical User Interface): A user-friendly interface that utilizes visual elements such as icons and menus to allow users to easily interact with the operating system.

Hypervisor: Advanced virtualization software that allows multiple operating systems to run on the same physical hardware, enabling efficient resource sharing and consolidation.

IDE (Integrated Development Environment): A comprehensive software application that provides a wide range of tools for writing, debugging, and testing code, streamlining the software development process.

Inheritance: A programming concept that allows a class to inherit properties and methods from a parent class, promoting efficient code reuse and modularity.

Interrupt: A signal sent to the operating system by a hardware device or software program to request immediate attention or services.

Kernel: The central component of an operating system that manages the hardware and software resources of a computer, enabling the smooth execution of user programs.

“The kernel is the heart of the operating system and controls all the important functions of hardware – this is the case for Linux, macOS and Windows, smartphones, servers, and virtualizations like KVM as well as every other type of computer.” Source

Library: A repository of compiled code that can be linked into a program to perform specialized tasks.

Linker: A program that combines object code files and libraries into a cohesive executable file.

Load balancing: The strategic distribution of workloads across multiple computers or servers to optimize performance and reliability.

Malware: A malicious software designed to harm or exploit a computer system.

Memory management: The judicious allocation and deallocation of memory to and from processes and programs.

Monitors: A synchronization object that allows multiple threads to access a shared resource in a controlled manner, utilizing a lock and conditional variables.

Mutex: A synchronization object that exclusively allows one thread to access a shared resource at a time.

Network adapter: A hardware device that connects a computer to a network.

Network file system (NFS): A protocol enabling a computer to access files on another computer over a network as if they were stored on its own local hard drive.

Network protocol: A set of rules and standards that govern the communication between devices on a network.

Network security: Measures taken to secure a network and its data from unauthorized access or attacks.

Network share: A resource, such as a file or printer, that is made accessible to other devices on a network.

Network-attached storage (NAS): A device that connects to a network and provides file-based data storage services.

Object-oriented programming (OOP): A programming paradigm that utilizes the concept of objects and their interactions to achieve its objectives.

Patch: A small yet crucial update that rectifies a specific issue within an operating system or software program.

“When software updates become available, vendors usually put them on their websites for users to download. Install updates as soon as possible to protect your computer, phone, or other digital device against attackers who would take advantage of system vulnerabilities.” Source

Plugin: A software extension that adds specialized and often unique functionality to an application.

Polymorphism: A programming concept that allows objects of different classes to be treated as a single, unified type, permitting them to be used interchangeably and adaptively.

Priority: A value that determines the order in which processes and threads are scheduled for execution, with higher priorities being given precedence over lower priorities.

Process: An instance of a program being actively executed by the computer.

Race condition: A scenario in which the outcome of a process is dependent on the timing of other processes, resulting in unpredictable and often undesirable outcomes.

Ransomware: A nefarious type of malware that encrypts a victim’s data and demands a ransom for its restoration, often causing significant disruption and damage to the victim’s systems.

Recovery disk: A removable storage device, such as a USB drive or CD, that contains a copy of the operating system and can be utilized to restore the system in the event of failure or disaster.

“A recovery disk is probably the most essential Windows component. Ideally, it helps us reinstall Windows in case of a system failure or any other unwanted issue.” Source

Related: Backup & Disaster Recovery

Recovery partition: A dedicated area on a hard drive that contains a copy of the operating system and can be utilized to restore the system in the event of failure or disaster.

Redundant array of independent disks (RAID): A system that employs multiple disks in an intelligent and redundant manner, providing enhanced performance, capacity, and reliability for the user.

Registry: A comprehensive database of system and program settings on a Windows operating system, utilized to store vital configuration and customization information.

Rootkit: A malicious program cleverly crafted to penetrate the kernel of an operating system, allowing it to manipulate and execute hazardous code without detection.

SDK (Software Development Kit): A set of tools and resources that are used to develop software applications.

Scheduler: The scheduler plays a pivotal role in the OS, as it ensures that all processes and threads are optimally allocated and managed for maximum efficiency.

Semaphore: An efficient synchronization tool for managing simultaneous access to a shared resource among multiple threads.

Service: An unobtrusive program that executes a designated task or mission in the background.

Shortcut: Need to quickly access a file, folder, or program? A shortcut is the answer! It’s an easy-to-use link that will take you directly to where you need go. Save time by setting up shortcuts on your desktop – it only takes a couple of seconds and then all of your frequently used items are just one click away.

Shutdown: Powering down a computer, thus ending its current session.

Spyware: Unbeknownst to users, Spyware can infiltrate computers and monitor any action taken online.

Startup folder: When you store programs and scripts in the startup folder, they will be launched as soon as your computer is powered on. This makes it easy to access frequently used applications without needing to open them manually each time.

Storage Area Network (SAN): Harness the power of a Storage Area Network (SAN) to maximize server efficiency and speed. SANs are dedicated, high-speed networks that link storage devices directly to servers for optimal performance.

Structured programming: A programming paradigm that is based on the use of control structures, such as loops and conditional statements, to organize code into logical blocks.

Swap space: A hard drive section employed as virtual memory when the physical RAM is overwhelmed and can no longer take on additional information.

System backup: A copy of all or some of the data and settings on a computer, made for the purpose of restoration in case of data loss or system failure.

System call: When a program needs assistance from the operating system to complete an assigned task or service, we call this a ‘system call’. It is essentially the bridge between the application and its underlying processes.

System log: A comprehensive summary of system events and messages that is invaluable for troubleshooting and assessment.

System monitor: A powerful tool that offers instantaneous insight into a computer’s functioning and resource utilization.

System restore: The process of returning a computer to a previous state using a system backup.

System tray: An area on the taskbar that displays icons for system and program features, such as the volume control and network status.

Task manager: A powerful tool that enables users to efficiently monitor and manage their computer’s resources. With this helpful utility, you can easily keep track of the processes running on your computing device and make sure everything runs smoothly.

Taskbar: A bar at the bottom of the screen that displays the open programs and allows users to switch between them.

Thread: Threads are an invaluable tool for modern computing, a lightweight process that can be generated within any given program and still remain independent from other processes running concurrently.

Trojan: A malevolent form of software that deceives the user by masquerading as a safe or legitimate application.

Update: A modification to an operating system or software program that fixes bugs or adds new features.

Virtual memory: A form of extended storage that acts as an extension to a computer’s physical RAM, increasing its total capacity.

Virtual Private Network (VPN): Leverage the power of a Virtual Private Network (VPN) to keep your data secure while navigating public networks, like the internet. VPNs provide an extra layer of protection by encrypting communication for maximum privacy and security.

Virtualization: The process of creating a virtual version of a hardware device or operating system.

Virus: Viruses are a malicious form of malware that can self-replicate and quickly spread between computers, wreaking havoc on unsuspecting networks.