Top 100 Linux Interview questions

  

1. cd — Change directory
2. ls — List directory contents
3. pwd — Print working directory
4. cat — Concatenate and display files
5. touch — Create an empty file
6. cp — Copy files and directories
7. mv — Move or rename files and directories
8. rm — Remove files and directories
9. mkdir — Create a new directory
10. rmdir — Remove an empty directory
11. cut — Cut out sections of a file
12. gzip — Compress or decompress files using gzip
13. gunzip — Decompress files compressed with gzip
14. find — Find files and directories matching a pattern
15. grep — Search for a pattern in a file
16. awk — Pattern scanning and processing language
17. sed — Stream editor for filtering and transforming text
18. head — Display the first few lines of a file
19. tail — Display the last few lines of a file
20. sort — Sort lines of a file
21. uniq — Remove duplicate lines from a file
22. wc — Count lines, words, and characters in a file
23. diff — Compare two files line by line
24. patch — Apply a patch to a file
25. chmod — Change permissions of files and directories
26. chown — Change the owner of a file or directory
27. chgrp — Change the group ownership of a file or directory
28. ps — List running processes
29. top — Display system resource usage and process information
30. kill — Send a signal to a process to terminate it
31. du — Display disk usage of files and directories
32. df — Display free disk space on the file system
33. mount — Mount a file system
34. umount — Unmount a file system
35. ping — Test connectivity to a network host
36. ssh — Secure shell remote login and command execution
37. scp — Secure copy files between hosts
38. rsync — Remote file and directory synchronization
39. curl — Transfer data from or to a server using various protocols
40. wget — Retrieve files from the web using various protocols
41. ftp — File Transfer Protocol client
42. sftp — Secure File Transfer Protocol client
43. telnet — Telnet client
44. nslookup — DNS lookup utility
45. dig — DNS lookup utility
46. netstat — Display network connections and statistics
47. ifconfig — Configure network interfaces
48. route — Display or modify the routing table
49. iptables — Firewall and packet filtering utility
50. hostname — Display or set the hostname of the system
51. date — Display or set the system date and time
52. timedatectl — Control the system date and time
53. uname — Display system information
54. whoami — Display the current user ID
55. id — Display user and group information
56. su — Switch user to become another user
57. sudo — Execute a command with superuser privileges
58. passwd — Change the password of a user account
59. useradd — Create a new user account
60. userdel — Delete a user account
61. usermod — Modify a user account
62. groupadd — Create a new group
63. groupdel — Delete a group
64. groupmod — Modify a group
65. finger — Display information about users on the system
66. last — Display information about recent logins
67. history — Display command history
68. echo — Print a message to the terminal
69. printf — Format and print data
70. lshw — Displays hardware information
71. lspci — Displays information about PCI buses and devices.
72. lsusb — Displays information about USB buses and devices.
73. hwinfo — Displays detailed hardware information.
74. free — Displays memory usage.
75. vmstat — Displays system memory, processor, and I/O statistics.
76. iostat — Displays CPU and disk I/O statistics.
77. uptime — Displays system uptime and load averages.
78. journalctl — Displays the system journal.
79. dmesg — Displays the kernel ring buffer.
80. crontab — Schedules recurring tasks.
81. at — Schedules a one-time task.
82. service — Manages system services.
83. systemctl — Controls system services in systemd-based distributions.
84. traceroute — Traces the network path to a remote host.
85. bzip2 — Compresses files using the bzip2 algorithm.
86. unzip — Extracts files from a ZIP archive.
87. tee — Redirect output to multiple files
88. chroot — Change the root directory for a process
89. ps aux — Display information about all running processes
90. less — Display file contents in a paginated format
91. more — Display file contents one page at a time
92. ln — Create links between files
93. realpath — Print the resolved absolute path of a file
94. watch — Execute a command periodically and display the output
95. cal — Display a calendar
96. tar -xzvf — Extract files from a compressed archive
97. tar -czvf — Create a compressed archive
98. whereis — Locate the binary, source, and manual page files for a command
99. locate — Find files by name
100. which — Display the full path to an executable