Linux Terms Glossary

Linux, a powerful and versatile operating system, has a rich vocabulary that can be daunting for newcomers. To help you navigate this terminology, here’s a concise explanation of 100 common Linux terms:

Common Linux Terms

A

• Absolute Path: A full path to a file or directory starting from the root directory (/), specifying the complete location in the file system.
• Access Control Lists (ACL): A method of defining more granular permissions for files and directories beyond the standard read, write, and execute permissions.
• Administrator (root): The superuser account with complete system access and control, typically with user ID 0.
• Alias: A custom shortcut or alternative name for a command, created to simplify complex commands or provide easier-to-remember command names.
• Apache: An open-source web server software widely used for hosting websites and web applications.

B

• Bash (Bourne Again Shell): The default command-line shell on most Linux distributions, providing a text-based interface for interacting with the operating system.
• Bind Mount: A method of mounting a directory or file at another location, creating a mirror or link to the original location.
• BIOS (Basic Input/Output System): Firmware used to perform hardware initialization during the booting process and to provide runtime services for operating systems.

C

• Cgroups (Control Groups): A Linux kernel feature that limits, accounts for, and isolates resource usage of process collections.
• Chroot: A Unix operation that changes the apparent root directory for the current running process, creating an isolated environment.
• CLI (Command Line Interface): A text-based interface for interacting with the computer by typing commands.
• Compiler: A program that translates source code written in a high-level programming language into machine code.
• Cron: A time-based job scheduler in Unix-like operating systems for running scheduled tasks.

D

• Daemon: A background process that runs continuously, typically started at system boot and often providing system services.
• Desktop Environment: A collection of software that provides a graphical user interface and a suite of applications.
• Distribution (Distro): A complete Linux operating system package that includes the Linux kernel, system utilities, and software applications.
• Docker: A platform for developing, shipping, and running applications in containers.

E

• EFI (Extensible Firmware Interface): A modern replacement for the traditional BIOS, used in booting computers.
• Environment Variable: A dynamic-named value that can affect the way running processes behave on a computer.
• Ext4 (Fourth Extended Filesystem): A widely used Linux filesystem that supports large file systems and improvements over previous ext versions.

F

• Firewall: A network security system that monitors and controls incoming and outgoing network traffic.
• File Permissions: A system of access rights that determines who can read, write, or execute a file.
• FOSS (Free and Open Source Software): Software that is both free to use and has its source code openly available.

G

• GNOME: A popular open-source desktop environment for Linux systems.
• Grep: A command-line utility for searching text using pattern matching.
• GUI (Graphical User Interface): A visual way of interacting with a computer using windows, icons, and menus.

H

• Hardlink: A directory entry pointing to the same inode as another file, creating multiple names for the same file content.
• Hostname: The name assigned to a computer on a network to identify it.
• Hypervisor: Software that creates and runs virtual machines.

I

• inode: A data structure that stores metadata about a file in a filesystem.
• IP Address: A unique identifier assigned to a device on a computer network.
• ISO: A disk image file format commonly used for distributing Linux distributions.

K

• Kernel: The core of the Linux operating system that manages system resources and provides essential services.
• KDE: Another popular desktop environment for Linux systems.
• Kernel Module: A piece of code that can be loaded and unloaded into the kernel to extend its functionality.

L

• LAMP Stack: A set of open-source software (Linux, Apache, MySQL, PHP/Python/Perl) used for web development.
• Lightweight Desktop Environment: A less resource-intensive desktop environment designed for older or less powerful computers.
• Locale: Settings that define language, country, and character encoding preferences.

M

• Mount: The process of making a filesystem available at a specific point in the directory tree.
• Multiplex: Running multiple terminal sessions within a single window.
• MIME Type: A standard that indicates the nature and format of a document, file, or assortment of bytes.

N

• Namespace: A Linux kernel feature that provides isolation for system resources.
• Network Socket: An endpoint for communication between two machines.
• NFS (Network File System): A protocol that allows file sharing across a network.

O

• Open Source: Software with source code that is freely available for modification and redistribution.
• Overlay Filesystem: A filesystem method that allows one filesystem to be layered on top of another.

P

• Package Manager: A tool for installing, upgrading, configuring, and removing software packages.
• Pipe (|): A method of connecting the output of one command to the input of another.
• POSIX: A family of standards specified by the IEEE to maintain compatibility between operating systems.

Q

• Quota: A system for limiting disk space usage for users or groups.

R

• RAID (Redundant Array of Independent Disks): A data storage virtualization technology that combines multiple physical disk drive components.
• Relative Path: A path to a file or directory relative to the current working directory.
• Repository: A storage location for software packages.
• Rice: It refers to the process of customizing your operating system’s appearance and functionality to your personal preferences. It involves tweaking various aspects of your desktop environment.

S

• SSH (Secure Shell): A cryptographic network protocol for secure data communication.
• Symlink (Symbolic Link): A special type of file that points to another file or directory.
• Sudo: A command that allows authorized users to execute commands with elevated privileges.

T

• Tar: A utility for archiving files.
• Terminal: A text input/output environment where users can enter commands.
• Timezone: A region of the globe that observes a uniform standard time.

U

• udev: A device manager for the Linux kernel.
• Umask: A command that determines the default permissions for new files and directories.
• User Space: The area of memory where user applications run, separate from kernel space.

V

• Virtual Machine: An emulation of a computer system running on another computer.
• Vi/Vim: A powerful text editor included in most Linux distributions.

W

• Wget: A command-line utility for retrieving files using HTTP, HTTPS, and FTP protocols.
• Wildcard: Special characters used to perform pattern matching in file and directory names.

X

• X Window System: The standard toolkit and protocol for building graphical user interfaces on Unix-like systems.
• XFCE: A lightweight desktop environment.
• Xorg: The most common implementation of the X Window System.

Z

• Zsh: An advanced shell with many improvements and features over Bash.
• Zombie Process: A process that has completed execution but still has an entry in the process table.