| No. | Item | Definition |
|---|---|---|
| 1. | ACL | extended file permission list |
| 2. | alias | custom command shortcut |
| 3. | AppArmor | path-based security framework |
| 4. | apt | Debian package manager command |
| 5. | awk | text processing language |
| 6. | bash | common Unix shell |
| 7. | boot | system startup process |
| 8. | bootloader | program that starts the kernel |
| 9. | cat | display file contents |
| 10. | chgrp | change file group |
| 11. | chmod | change file permissions |
| 12. | chown | change file owner |
| 13. | command | instruction entered at the shell |
| 14. | cp | copy files or directories |
| 15. | CPU | main processor resource |
| 16. | cron | time-based job scheduler |
| 17. | daemon | background service process |
| 18. | df | show filesystem free space |
| 19. | directory | folder in the filesystem |
| 20. | disk | storage device |
| 21. | dmesg | kernel message viewer |
| 22. | dnf | Fedora package manager command |
| 23. | DNS | name-to-address lookup system |
| 24. | du | show disk usage |
| 25. | environment | set of shell variables |
| 26. | fdisk | disk partitioning tool |
| 27. | file | named data stored on disk |
| 28. | filesystem | organized file storage hierarchy |
| 29. | find | search for files |
| 30. | firewall | network traffic filter |
| 31. | fsck | check and repair filesystem |
| 32. | fstab | filesystem mount configuration file |
| 33. | gateway | router to other networks |
| 34. | grep | search text by pattern |
| 35. | group | set of users |
| 36. | grub | common bootloader |
| 37. | gzip | compression program and format |
| 38. | head | show beginning of a file |
| 39. | hostname | system’s network name |
| 40. | init | first userspace process |
| 41. | inode | filesystem metadata record |
| 42. | interface | network connection point |
| 43. | IP address | numeric network identifier |
| 44. | journalctl | view systemd logs |
| 45. | kernel | core of the operating system |
| 46. | kill | send signal to a process |
| 47. | KVM | kernel virtual machine technology |
| 48. | less | text pager program |
| 49. | ln | create file links |
| 50. | load | system work level |
| 51. | log | record of system events |
| 52. | ls | list directory contents |
| 53. | LVM | logical volume management system |
| 54. | man | built-in manual system |
| 55. | memory | RAM used by programs |
| 56. | mkdir | create a directory |
| 57. | mkfs | create a filesystem |
| 58. | module | loadable kernel component |
| 59. | mount | attach a filesystem |
| 60. | mv | move or rename files |
| 61. | namespace | kernel isolation mechanism |
| 62. | owner | user who controls a file |
| 63. | package | installable software bundle |
| 64. | partition | disk subdivision |
| 65. | path | location string for a file |
| 66. | permission | access rule for files |
| 67. | ping | network reachability test |
| 68. | pipe | connect command outputs and inputs |
| 69. | port | numbered network endpoint |
| 70. | process | running program instance |
| 71. | RAID | redundant disk array method |
| 72. | reboot | restart the system |
| 73. | repository | software package source |
| 74. | rm | remove files or directories |
| 75. | root | superuser account |
| 76. | route | network path rule |
| 77. | rsync | efficient file synchronization tool |
| 78. | runlevel | legacy system operating state |
| 79. | scp | secure file copy command |
| 80. | script | file of shell commands |
| 81. | shell | command-line interpreter |
| 82. | SSH | secure remote login protocol |
| 83. | stderr | standard error stream |
| 84. | stdin | standard input stream |
| 85. | stdout | standard output stream |
| 86. | sudo | run commands with elevated privileges |
| 87. | symlink | symbolic file reference |
| 88. | systemd | system and service manager |
| 89. | tail | show end of a file |
| 90. | tar | archive creation utility |
| 91. | terminal | text interface for commands |
| 92. | thread | lightweight execution unit |
| 93. | top | interactive process viewer |
| 94. | touch | create file or update timestamp |
| 95. | umask | default permission mask |
| 96. | uptime | time since last boot |
| 97. | user | account on the system |
| 98. | UUID | unique device identifier |
| 99. | variable | named stored value |
| 100. | virtualization | running virtual machines |