Unix glossary Page
Unix Glossary
Return to Unix, Linux Glossary, Debian Glossary, Fedora Glossary
----
* Provide a Unix glossary of the top 75 Unix concepts sorted by the most commonly used. For each concept include a brief description and the URL for the Unix official documentation and the appropriate GitHub repo or other source code repository. Answer using MediaWiki format.
Creating a detailed Unix glossary with 75 concepts, including descriptions, URLs for official documentation, and links to GitHub repositories or other source code repositories where applicable, poses a significant challenge due to the diversity and breadth of Unix-like systems and the varying availability of official documentation and source code. Given these constraints, I will focus on general concepts applicable across many Unix-like systems, providing URLs for widely recognized documentation sources and repositories where possible. Note that not all Unix concepts have a specific GitHub repository, especially for proprietary systems, but I'll include relevant links where available.
```mediawiki
= Unix Glossary =
1. Shell
The interface used by users to interact with the operating system, often through a command-line interface (CLI).
[Documentation: https://www.gnu.org/software/bash/manual/]
2. Kernel
The core of the Unix operating system, managing hardware resources and system calls.
[Documentation: https://www.kernel.org/doc/]
3. File System
The structure and logic used to manage files and directories on storage devices.
[Documentation: https://tldp.org/LDP/intro-linux/html/sect_03_01.html]
4. Process
An instance of a running program, including its code and current activity.
[Documentation: https://tldp.org/LDP/tlk/kernel/processes.html]
5. PID (Process ID)
A unique identifier assigned to each process running on the system.
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/proc.html]
6. Signals
Notifications sent to a process to request a change in state or to communicate.
[Documentation: https://www.gnu.org/software/libc/manual/html_node/Signal-Handling.html]
7. Pipes and Redirection
Tools for directing the output of one command to the input of another.
[Documentation: https://tldp.org/LDP/abs/html/io-redirection.html]
8. Users and Groups
The system for managing access through user IDs (UIDs) and group IDs (GIDs).
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/chap03.html]
9. Permissions
The access rights granted to users and groups for files and directories.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1089.htm]
10. Vi/Vim
A powerful text editor available in most Unix systems.
[Documentation: https://www.vim.org/docs.php]
[Source: https://github.com/vim/vim]
11. grep
A command-line utility for searching text using regular expressions.
[Documentation: https://www.gnu.org/software/grep/manual/grep.html]
[Source: https://git.savannah.gnu.org/cgit/grep.git/]
12. sed
A stream editor for filtering and transforming text.
[Documentation: https://www.gnu.org/software/sed/manual/sed.html]
[Source: https://git.savannah.gnu.org/cgit/sed.git/]
13. awk
A programming language designed for text processing.
[Documentation: https://www.gnu.org/software/gawk/manual/gawk.html]
[Source: https://git.savannah.gnu.org/cgit/gawk.git/]
14. Cron
A daemon to execute scheduled commands.
[Documentation: https://www.gnu.org/software/mcron/manual/mcron.html]
15. SSH (Secure Shell)
A protocol for secure remote communication.
[Documentation: https://www.openssh.com/manual.html]
[Source: https://github.com/openssh/openssh-portable]
16. File Commands (ls, cd, cp, mv, mkdir, rm)
Basic commands for managing files and directories.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1089.htm]
17. Networking Commands (ifconfig, ping, netstat)
Commands for managing and troubleshooting network configurations.
[Documentation: https://tldp.org/LDP/nag2/x-087-2-iface.ifconfig.html]
18. System Monitoring (top, ps, free, df)
Tools for assessing system performance and resources.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1085.htm]
19. Package Management (apt, yum, rpm)
Systems for managing software packages.
[Documentation: https://debian-handbook.info/browse/stable/sect.package-management.html]
20. Disk Management (fdisk, mkfs, mount)
Commands for disk partitioning and file system management.
[Documentation: https://tldp.org/LDP/sag/html/partitions.html]
21. Environment Variables
Variables that affect the behavior of running processes.
[Documentation: https://tldp.org/LDP/Bash
-Beginners-Guide/html/sect_03_02.html]
22. Scripting
The writing of shell scripts to automate tasks.
[Documentation: https://tldp.org/LDP/abs/html/]
23. Syslog
A standard protocol for system logging.
[Documentation: https://tldp.org/LDP/sag/html/basic-chapter.html]
24. NFS (Network File System)
A protocol for distributed file systems.
[Documentation: https://tldp.org/HOWTO/NFS-HOWTO/intro.html]
25. Samba
A suite for sharing files and printers with Windows.
[Documentation: https://www.samba.org/samba/docs/]
[Source: https://github.com/samba-team/samba]
26. Swap Space
Disk space used to extend available physical memory.
[Documentation: https://tldp.org/LDP/sag/html/swap-space.html]
27. Inodes
Data structures used to store information about files.
[Documentation: https://tldp.org/LDP/tlk/fs/filesystem.html]
28. Links (Symbolic and Hard)
Pointers to files within the file system.
[Documentation: https://tldp.org/LDP/intro-linux/html/sect_03_05.html]
29. Tar and gzip
Utilities for file compression and archiving.
[Documentation: https://www.gnu.org/software/tar/manual/tar.html]
[Source (tar): https://git.savannah.gnu.org/cgit/tar.git/]
30. find and locate
Commands for searching the filesystem.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
31. Regular Expressions
Patterns used for matching text strings.
[Documentation: https://tldp.org/LDP/abs/html/x17129.html]
32. man Pages
The manual pages, a comprehensive documentation system.
[Documentation: https://tldp.org/LDP/man-pages/index.html]
33. Boot and Shutdown
The processes for starting up and shutting down Unix systems.
[Documentation: https://tldp.org/LDP/sag/html/boot-process.html]
34. Filesystem Hierarchy Standard (FHS)
A standard layout for Unix filesystems.
[Documentation: https://refspecs.linuxfoundation.org/FHS_3.0/fhs/index.html]
35. Dynamic Linking
Linking libraries to executables at runtime.
[Documentation: https://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html]
36. System Calls
Interfaces provided by the Unix kernel.
[Documentation: https://tldp.org/LDP/tlk/syscalls/syscalls.html]
37. DTrace
A tool for dynamic tracing of programs.
[Documentation: http://dtrace.org/guide/preface.html]
38. ACLs (Access Control Lists)
Extended permission systems on Unix files.
[Documentation: https://tldp.org/HOWTO/Access-Control-HOWTO/index.html]
39. LVM (Logical Volume Manager)
A framework for managing disk storage in a more flexible manner.
[Documentation: https://tldp.org/HOWTO/LVM-HOWTO/]
40. UNIX Domain Sockets
IPC mechanism for exchanging data between processes on the same host.
[Documentation: https://tldp.org/LDP/LG/issue93/bhaskaran.html]
41. Job Control
Mechanisms for managing multiple processes from a single shell.
[Documentation: https://tldp.org/LDP/abs/html/x9644.html]
42. Time Commands (date, cal)
Utilities for displaying and setting time and date.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1087.htm]
43. Umask
Determines default permissions for new files and directories.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x1770.htm]
44. chroot
Changes the root directory for a process and its children.
[Documentation: https://tldp.org/LDP/sag/html/chroot-bind.html]
45. SysVinit and Systemd
Init systems for managing processes at boot time.
[Documentation (Systemd): https://www.freedesktop.org/wiki/Software/systemd/]
[Source (Systemd): https://github.com/systemd/systemd]
46. iptables/firewalld
Tools for managing network packet filtering and firewall rules.
[Documentation: https://tldp.org/HOWTO/IPCHAINS-HOWTO.html]
47. SSH Key Management
The creation and management of keys for SSH authentication.
[Documentation:
https://www.ssh.com/ssh/keygen/]
48. umount
Command for detaching filesystems.
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/mnt.html]
49. du and df
Commands for disk usage and filesystem space reporting.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1085.htm]
50. nohup
Allows a command to continue running after logging out.
[Documentation: https://tldp.org/LDP/abs/html/x9644.html]
51. init
The first process started by the Unix kernel, spawning all other processes.
[Documentation: https://tldp.org/LDP/intro-linux/html/sect_04_02.html]
52. syslogd
The daemon for logging system messages.
[Documentation: https://tldp.org/LDP/sag/html/config-syslog.html]
53. /proc Filesystem
A virtual filesystem providing access to kernel and process information.
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/proc.html]
54. make
A tool for managing the build process of software from source code.
[Documentation: https://www.gnu.org/software/make/manual/make.html]
[Source: https://github.com/make-gnu/make]
55. Patch
A program for applying changes to text files, typically source code.
[Documentation: https://www.gnu.org/software/patch/manual/patch.html]
[Source: https://git.savannah.gnu.org/cgit/patch.git/]
56. diff
Compares files line by line.
[Documentation: https://www.gnu.org/software/diffutils/manual/diffutils.html]
[Source: https://git.savannah.gnu.org/cgit/diffutils.git/]
57. inetd/xinetd
Daemon programs that provide Internet services.
[Documentation: https://tldp.org/LDP/sag/html/basic-chapter.html]
58. Mount
The command to attach filesystems to a directory tree.
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/mnt.html]
59. umask Command
Sets the default creation permissions for new files and directories.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x1770.htm]
60. Alias
A way to create shortcuts for long commands or command sequences.
[Documentation: https://tldp.org/LDP/abs/html/aliases.html]
61. TTY
Terminals or console interfaces for interacting with the system.
[Documentation: https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/dev.html]
62. Load Average
A measure of system activity, indicating the average number of processes waiting for CPU time.
[Documentation: https://tldp.org/LDP/sag/html/load-average.html]
63. ulimit
A tool for controlling the resources available to the shell and processes started by it.
[Documentation: https://tldp.org/LDP/abs/html/limits.html]
64. Sticky Bit
A permission setting that when set on a directory, allows only the file's owner, the directory's owner, or root to delete the file.
[Documentation: https://tldp.org/LDP/sag/html/sticky-bit.html]
65. SUID and SGID
Special permission modes that execute a file with the permissions of the file owner or group.
[Documentation: https://tldp.org/LDP/sag/html/permissions.html]
66. chown
Changes the owner of a file or directory.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1089.htm]
67. chgrp
Changes the group ownership of a file or directory.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1089.htm]
68. whoami
Displays the username of the current user.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
69. who
Shows who is logged on the system.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
70. w
Displays who is logged on and what they are doing.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
71. last
Shows a listing of last logged in users.
[Documentation: https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
72. traceroute
A network diagnostic tool for displaying the route packets take to a network host.
[Documentation: https://tldp.org/LDP/nag/node82.html]
73. dig
A DNS lookup utility.
[Documentation: https://tldp.org/LDP/LG/issue18/dns.html]
74. iptables
A user-space utility program for configuring the Linux IPv4 packet filtering rules.
[Documentation: https://tldp.org/HOWTO/IPCHAINS-HOWTO.html]
75. nslookup
A network administration command-line tool for querying the Domain Name System (DNS) to obtain domain name or IP address mapping.
[Documentation: https://tldp.org/LDP/nag/node83.html]
```
Given the broad scope of Unix and Unix-like systems, the provided links are to general documentation that covers the concepts broadly or to specific tools within the GNU/Linux ecosystem, which represents a significant part of modern Unix-like environments. For proprietary Unix systems, you should consult the vendor's official documentation for the most accurate information.
----
* Provide a Unix glossary of the top 50 Unix concepts sorted by the most commonly used. For each concept include a brief description and the URL for the Unix official documentation. Answer using MediaWiki format.
Creating a comprehensive Unix glossary that encompasses the top 50 concepts requires considering a wide range of Unix-based operating systems and their documentation. Unlike FreeBSD, which has centralized documentation, Unix spans multiple variants like Linux, AIX, HP-UX, Solaris, and more, each with its documentation. For this reason, I'll provide a generic Unix glossary with descriptions of key concepts. For official documentation, I'll reference URLs where you can find broader Unix documentation or specific manuals, noting that for vendor-specific information (like AIX or Solaris), you should consult the vendor's official site.
Please note, the URLs for general Unix documentation will point to places where Unix documentation or related resources can be found, such as the Linux Documentation Project or the Open Group for POSIX standards, as there isn't a singular "official" Unix documentation source for all these concepts.
```mediawiki
= Unix Glossary =
1. Shell
The command-line interface used to interact with the operating system. Shells like bash, sh, and zsh allow users to execute commands, run scripts, and manage system tasks.
[https://www.gnu.org/software/bash/manual/]
2. Kernel
The core part of the Unix operating system, responsible for managing hardware, running processes, and system calls.
[https://www.kernel.org/doc/html/latest/]
3. File System
The method and data structure that the operating system uses to control how data is stored and retrieved.
[https://tldp.org/LDP/intro-linux/html/sect_03_01.html]
4. Process
A running instance of a program, including the program code and its current activity.
[https://tldp.org/LDP/tlk/kernel/processes.html]
5. PID (Process ID)
A unique number assigned to each process running in the system.
[https://tldp.org/LDP/tlk/kernel/processes.html]
6. Signals
A form of inter-process communication in Unix, used by processes to communicate with each other or with the kernel.
[https://www.gnu.org/software/libc/manual/html_node/Signal-Handling.html]
7. Pipes and Redirection
Mechanisms for directing the output of one command to the input of another, allowing for data to be processed and transferred between commands.
[https://tldp.org/LDP/abs/html/io-redirection.html]
8. Users and Groups
Unix systems manage access control through users and groups, assigning permissions and resources.
[https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/chap03.html]
9. Permissions
Unix file permissions control the read, write, and execute access for the owner, group, and others.
[https://tldp.org/LDP/intro-linux/html/sect_03_04.html]
10. Vi/Vim
A text editor available in Unix systems, known for its power and efficiency.
[https://www.vim.org/docs.php]
11. grep
A command-line utility for searching plain-text data sets for lines matching a regular expression.
[https://www.gnu.org/software/grep/manual/grep.html]
12. sed
A stream editor for filtering and transforming text in Unix-like systems.
[https://www.gnu.org/software/sed/manual/sed.html]
13. awk
A programming language and utility for text processing and data extraction.
[https://www.gnu.org/software/gawk/manual/gawk.html]
14. Cron
A time-based job scheduler in Unix-like operating systems for running scheduled tasks.
[https://www.gnu.org/software/mcron/manual/mcron.html]
15. SSH (Secure Shell)
A cryptographic network protocol for operating network services securely over an unsecured network.
[https://www.openssh.com/manual.html]
16. File and Directory Commands (ls, cd, cp, mv, mkdir, rm)
Basic commands for managing files and directories in Unix systems.
[https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1089.htm]
17. Networking Commands (ifconfig, ping, netstat)
Commands for managing network interfaces and troubleshooting network connections.
[https://tldp.org/LDP/nag2/x-087-2-iface.ifconfig.html]
18. System Monitoring Commands (top, ps, free, df)
Commands for monitoring system performance and resources.
[https://tldp.org/LDP/LG/issue48/fischer.html]
19. Package Management (apt, yum, rpm)
Systems and utilities for managing software packages in Unix-like systems.
[https://debian-handbook.info/browse/stable/sect.package-management.html]
20. Disk Management (fdisk, mkfs, mount)
Tools for managing disk partitions, file system creation, and mounting file systems.
[https://tldp.org
/LDP/sag/html/partitions.html]
21. Environment Variables
Variables that are defined in the shell and affect the behavior of processes.
[https://tldp.org/LDP/Bash-Beginners-Guide/html/sect_03_02.html]
22. Scripting
Writing shell scripts to automate tasks and procedures in Unix systems.
[https://tldp.org/LDP/abs/html/]
23. Syslog
A standard for message logging, allowing the collection and storage of logs.
[https://tldp.org/LDP/sag/html/basic-chapter.html]
24. NFS (Network File System)
A distributed file system protocol allowing a user on a client computer to access files over a network.
[https://tldp.org/HOWTO/NFS-HOWTO/intro.html]
25. SAMBA
A re-implementation of the SMB networking protocol, allowing Unix systems to communicate with Windows systems.
[https://www.samba.org/samba/docs/]
26. Swap Space
A portion of a hard disk used as an extension of the computer's physical memory.
[https://tldp.org/LDP/sag/html/swap-space.html]
27. Inodes
Data structures on a file system that store information about files and directories.
[https://tldp.org/LDP/tlk/fs/filesystem.html]
28. Symbolic and Hard Links
References to files in the filesystem, allowing files to be accessed by multiple paths.
[https://tldp.org/LDP/intro-linux/html/sect_03_05.html]
29. Tar and gzip
Utilities for compressing and packaging multiple files into a single archive file.
[https://www.gnu.org/software/tar/manual/tar.html]
30. find and locate
Commands for searching and locating files and directories based on criteria.
[https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x11655.htm]
31. Regular Expressions
A sequence of characters that define a search pattern, used by search utilities like grep.
[https://tldp.org/LDP/abs/html/x17129.html]
32. man Pages
The manual pages in Unix, providing documentation for commands and programs.
[https://tldp.org/LDP/man-pages/index.html]
33. Boot and Shutdown Procedures
Processes and commands involved in starting up and shutting down Unix systems.
[https://tldp.org/LDP/sag/html/boot-process.html]
34. Filesystem Hierarchy Standard (FHS)
A standard layout for Unix filesystem directories and their contents.
[https://refspecs.linuxfoundation.org/FHS_3.0/fhs/index.html]
35. Dynamic Linking
The process of linking libraries to programs at runtime rather than at compile time.
[https://tldp.org/HOWTO/Program-Library-HOWTO/shared-libraries.html]
36. System Calls
Interfaces provided by the Unix kernel for performing various low-level operations.
[https://tldp.org/LDP/tlk/syscalls/syscalls.html]
37. DTrace
A comprehensive dynamic tracing framework for performance analysis and troubleshooting.
[http://dtrace.org/guide/preface.html]
38. ACLs (Access Control Lists)
A more flexible permission system on Unix that provides detailed access control to files and directories.
[https://tldp.org/HOWTO/Access-Control-HOWTO/index.html]
39. LVM (Logical Volume Manager)
A device mapper framework that provides logical volume management for the Linux kernel.
[https://tldp.org/HOWTO/LVM-HOWTO/]
40. UNIX Domain Sockets
A form of IPC (Inter-Process Communication) that allows data exchange between processes on the same machine.
[https://tldp.org/LDP/LG/issue93/bhaskaran.html]
41. Job Control
Mechanisms provided by Unix shells for managing multiple processes.
[https://tldp.org/LDP/abs/html/x9644.html]
42. Time Commands (date, cal)
Commands for displaying and setting the system time and date.
[https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1087.htm]
43. Umask
The default permission or file mode creation mask.
[https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/x1770.htm]
44. chroot
A command that changes the root directory for the current running process and its children.
[https://tldp.org/LDP/sag/html/chroot-bind.html]
45. SysVinit and Systemd
Init systems used to bootstrap the user space and manage system processes after booting.
[https://
tldp.org/LDP/intro-linux/html/sect_04_02.html]
46. iptables/firewalld
Tools for configuring and managing packet filtering and firewall rules.
[https://tldp.org/HOWTO/IPCHAINS-HOWTO.html]
47. SSH Key Management
The creation and management of SSH keys for secure, passwordless authentication.
[https://www.ssh.com/ssh/keygen/]
48. umount
The command used to unmount file systems.
[https://tldp.org/LDP/Linux-Filesystem-Hierarchy/html/mnt.html]
49. du and df
Commands for reporting the disk space usage of files and file systems.
[https://tldp.org/LDP/GNU-Linux-Tools-Summary/html/c1085.htm]
50. nohup
A command to run another command that ignores the HUP (hangup) signal.
[https://tldp.org/LDP/abs/html/x9644.html]
```
This glossary provides a foundation for understanding Unix concepts, but it's essential to consult specific documentation for the Unix variant you're using for detailed guidance and procedures. Remember, the URLs provided are general guides and may lead to resources beyond official documentation due to the diverse nature of Unix systems.
----
Unix on the Cloud
Unix VMs on Cloud Providers:
* aws>Unix on AWS.amazon.com
* ms>Unix on docs.microsoft.com
* gcp>Unix on cloud.google.com
* ibm>Unix on IBM.com
* oracle>Unix on docs.oracle.com
* vmware>Unix on VMware.com
Unix on Containers
* k8s>Unix on Kubernetes.io
* docker>Unix on Docker.com
* dockerhub>Unix on hub.docker.com (Docker Hub)
* podman>Unix on Podman.io
* quay>Unix on Quay.io
* helm>Unix on artifacthub.io
Unix Courses
* pluralsight>Unix on Pluralsight.com
* udemy>Unix on Udemy
* linkedinlearning>Unix on LinkedIn Learning
Fair Use Source
Fair Use Sources:
* ddg>Unix on DuckDuckGo
* google>Unix on Google
* github>Unix on GitHub
* oreilly>Unix on O'Reilly
* superuser>Unix on SuperUser.com
* stackoverflow>Unix on Stackoverflow
* reddit>Unix on Reddit
* youtube>Unix on YouTube
* archive>Unix for Archive Access for Fair Use Preservation, quoting, paraphrasing, excerpting and/or commenting upon
* distrowatch>Unix on distrowatch.com
* linuxfoundation>Unix on linuxfoundation.org
* linuxq>Unix on wiki.linuxquestions.org
* shell>Unix on shellhacks.com
* linuxhint>Unix on linuxhint.com
* linux>Unix on www.linux.org
* man>Unix on man.cx
* askubuntu>Unix on askubuntu.com
* ubuntuwiki>Unix on help.ubuntu.com/community
* debian>Unix on debian.org
* debianpkg>Unix on packages.debian.org
* debianwiki>Unix on wiki.debian.org
* redhat>Unix on developers.redhat.com
* fedora>Unix on fedoraproject.org
* fedoradocs>Unix on docs.fedoraproject.org
* archwiki>Unix on wiki.archlinux.org
* snap>Unix on snapcraft.io
* freebsd>Unix on forums.freebsd.org
{{navbar_unix}}
{{navbar_macos}}
{{navbar_freebsd}}
{{navbar_footer}}