Important Linux terms

Names and abbreviations you should know

Here's a list of important terms you should know when working with Linux:

API: Application Programming Interface, a set of rules that allows software applications to communicate with each other.
Arch: A popular Linux distribution known for its rolling release model.
Block device: The building block of storage.
Bootloader: A program that loads the operating system into memory when the computer starts.
BSD: Berkeley Software Distribution, a family of Unix-like operating systems.
Btrfs: A modern copy-on-write file system for Linux, known for advanced features such as snapshots and self-healing.
CentOS: A community-driven Linux distribution based on Red Hat Enterprise Linux (RHEL).
Certificate: A method to enable secure communications.
CGroup: A Linux kernel feature that limits and isolates the resource usage of a group of processes.
CIFS: Common Internet File System, a protocol for file sharing in Windows networks.
CMS: Content Management System, software for creating, managing, and modifying digital content.
Command line interface or CLI: A text-based interface for interacting with the operating system.
Container: A lightweight, isolated environment for running applications and their dependencies.
CPU: Central Processing Unit, the primary component of a computer that performs most of the processing inside a system.
Cron: A time-based job scheduler in Linux-like operating systems.
Daemon: A background process that runs on a Linux system.
Database: An organized structure for data.
Data center: A facility that houses computing resources like servers, storage, and networking equipment.
Debian: A popular Linux distribution.
Dependency: > The relationship between software packages.
Device: A physical or virtual component that is accessible to the system.
Device mapper: A kernel component to manage block devices.
DevOps: A set of practices that combines software development (Dev) and IT operations (Ops) to shorten the development lifecycle.
DHCP: Dynamic Host Configuration Protocol, a service that assigns IP addresses to devices on a network.
Directory: A container for files and other directories.
Distro: Short for distribution, a version of Linux with its own set of packages and tools.
DKIM: DomainKeys Identified Mail, an email authentication method that helps protect against email spoofing.
DMA: Direct Memory Access, a feature that allows hardware components to directly read from and write to memory without CPU intervention.
DMARC: Domain-based Message Authentication, Reporting & Conformance, a protocol for email authentication that helps prevent phishing and spoofing.
DNS: Domain Name System, a service that translates domain names to IP addresses.
ext2: Second Extended File System, an older Linux file system known for stability but lacking features like journaling.
ext3: Third Extended File System, a journaled version of ext2, providing improved reliability and crash recovery.
ext4: A popular file system for Linux.
FAT: A popular file system for USB sticks.
Fedora: A popular Linux distribution sponsored by Red Hat.
File: A collection of data stored on a Linux system.
Firewall: A network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.
FTP: File Transfer Protocol, a standard for transferring files over a network.
Gentoo: A popular Linux distribution known for its flexibility and customization options.
gid: The identifier for a group.
Group: A collection of users that can be assigned permissions as a single unit.
Grub: A boot loader for Linux systems.
GUI: Graphical User Interface
Hard link: A directory entry that associates a name with an existing file, allowing multiple paths to refer to the same file content.
HTTP: Hypertext Transfer Protocol, the foundation of data communication on the World Wide Web.
HTTPS: Secure Hypertext Transfer Protocol, an extension of HTTP with encryption for secure communication over a computer network.
Hypervisor: A software that allows multiple virtual machines to run on a single physical host.
ICMP: Ping to test if a server replies.
IMAP: Internet Message Access Protocol, a standard for accessing email on a mail server.
inetd: Manage internet services through a single daemon
Init System: Software that initializes the user space and manages system services after the Linux kernel has booted.
Inode: A data structure in a Unix-style file system that stores information about a file or directory, such as its size, owner, and permissions.
IOWait: A metric for measuring performance.
IRQ: A hardware signal to the CPU.
JSON: JavaScript Object Notation, a lightweight data-interchange format that is easy for humans to read and write and for machines to parse and generate.
KDC: Key Distribution Center, a component of the Kerberos protocol responsible for issuing and validating authentication tickets.
Kerberos: A network authentication protocol that uses secret-key cryptography.
Kernel: The core of the operating system that manages system resources and communicates with hardware.
Key-value store: A type of non-relational database that stores data as a collection of key-value pairs.
Kubernetes: An open-source platform for automating the deployment, scaling, and operation of containerized applications.
KVM: Kernel-based Virtual Machine, a Linux kernel module that allows the creation and management of virtual machines.
LAMP: A software stack for web development, consisting of Linux, Apache, MySQL, and PHP/Perl/Python.
LDAP: Lightweight Directory Access Protocol, a standard for storing and retrieving directory information.
libpcap: A library for network traffic capture, used in packet analysis tools like tcpdump and Wireshark.
Linux: An open-source operating system kernel that forms the basis for a variety of distributions, known for its stability, security, and flexibility.
Load average: A measure for system performance.
Logging: Recording of events that have occurred on a Linux system.
LVM: Logical Volume Manager, a system for managing and organizing disk storage.
Man page: Documentation for commands and functionalities.
Monitoring: Observing the health of a server.
Mounting: Making data on a device accessible.
MTA: Mail Transfer Agent, software responsible for transferring email messages from one computer to another.
NAT: Network address translation.
NFS: Network File System, a protocol for sharing files over a network.
NIC: Network Interface Card, a hardware component that connects a computer to a network.
NSS: Name Service Switch, a system used by the GNU C Library to determine sources from which to obtain name-service information in a range of categories, such as host names and user information.
NTFS: Microsoft's file system for Linux.
NTP: Network Time Protocol, a service that synchronizes the clocks of networked devices.
Operating system: A software layer between hardware and applications.
OSI Model: A layered structure for networking and communication protocols.
Package: A collection of software that can be installed and managed as a single unit.
Partition: A section of a storage device that is set aside for a specific use or file system.
Permission: The level of access a user or group has to a file or directory.
PID: The identifier of a running process.
Pipe: A feature that allows the output of one command to be used as the input for another command.
Pod: In Kubernetes, a Pod is the smallest deployable unit that can contain one or more containers.
POP3: Post Office Protocol version 3, a standard for retrieving email from a mail server.
Posix: Portable Operating System Interface, a set of standards for maintaining compatibility between operating systems.
Process: A program that is currently running on a Linux system.
Protocol: A formal definition how data is being transmitted.
QEMU: Quick Emulator, an open-source machine emulator and virtualizer that can run operating systems and programs for different hardware architectures.
RAID: Redundant Array of Independent Disks, a system for providing data redundancy and increased performance.
RDP: A protocol for remotely accessing Windows servers.
Repository: A collection of packages that can be installed on a Linux system.
Root: The superuser account on a Linux system.
Runlevel: A mode of operation in Unix-like operating systems that determines which services and processes are running.
SCP: Secure Copy Protocol, a command-line utility for securely transferring files over SSH.
SELinux: A security enhancement to the Linux kernel that provides a mechanism for supporting access control policies.
Service: A program that runs in the background and provides a specific function.
SFTP: Secure File Transfer Protocol, a secure variant of FTP that uses SSH for encryption.
Shell: A command-line interface that allows users to interact with the operating system.
Slackware: A popular Linux distribution known for its simplicity and stability.
SMTP: Simple Mail Transfer Protocol, a standard for sending email.
SNMP: Simple Network Management Protocol, a standard for monitoring network devices.
SPF: Sender Policy Framework, an email authentication method that helps prevent email spoofing.
SSH: A protocol for securely connecting to remote servers.
SSH key: A key pair for securely logging in to a remote server over SSH.
SSL: Secure Sockets Layer, a protocol for establishing encrypted links between a web server and a browser.
StdIn: Standard Input, a stream from which a program reads its input data.
StdOut: Standard Output, a stream to which a program writes its output data.
Superuser: The root account on a Linux system.
Swap: A space on a disk that is used as virtual memory when the physical memory is full.
Symlink: A special type of file that points to another file or directory.
Sysadmin: System Administrator, a person responsible for maintaining, configuring, and ensuring the reliable operation of computer systems.
Syslog: A standard for logging system events.
Systemd: A system and service manager for Linux that provides a suite of tools for managing system processes and services.
SysVinit: A traditional init system used in Unix-like operating systems to bootstrap the user space and manage system services.
TCP: A widely used communication protocol.
Terminal: A program that provides a command-line interface.
Timezone: A way to organize times around the globe
TLS: Transport Layer Security, a protocol that provides privacy and data integrity between two communicating applications.
TTY: Teletypewriter, a terminal device that provides a text-based interface to the system.
Ubuntu: A popular Linux distribution based on Debian.
UDP: A widely used communication protocol.
uid: The identifier of a user.
Unix: A family of multitasking, multiuser operating systems that originated in the 1960s and 1970s.
Upstart: An event-based init system used to manage tasks and services during boot, shutdown, and system operation.
User: A regular account on a Linux system.
UTC: Coordinated Universal Time, the primary time standard by which the world regulates clocks and time.
UUID: An identifier that is almost unique.
VFAT: A file system for USB drives.
Virtual machine: A simulation of a computer system, created using virtualization software.
Virtualization: The process of creating a virtual environment on a physical machine, allowing multiple operating systems to run on the same hardware.
VNC: A protocol for remotely accessing graphical desktop environments.
Web server: A server that hosts websites and serves content over the web using protocols like HTTP and HTTPS.
XFS: A file system for linux.
ZFS: Another file system for linux.