1. ip – used to show or manipulate routing, devices, and tunnels.
2. ls – list the contents of a directory.
3. df – Displays the amount of disk space used.
4. du – display a list of all the files along with their respective sizes.
5. free -h – use to get a detailed report on the system’s memory usage.
6. scp – securely copy files or directories over ssh.
7. find – locates files using user-defined criteria.
8. ncdu – provides a useful and convenient way to view disk usage.
9. pstree – used to show running processes in a tree (data structure).
10. latest – displays a list of the most recently logged-in people.
11. w – display a list of the currently logged-in user sessions.
12. grep – searches a file for a pattern of characters and displays all lines that match.
13. awk – a scripting language used for text processing.
14. sed – stream editor used to perform lots of functions on files, like searching, find and replace, insertion, or deletion.
15. cut – allows you to cut out sections of a specified file or piped data and print the result to standard output.
16. sort – used to sort files
17. uniq – used to extract uniq occurrences
18. tr – utility for translating or deleting characters.
19. diff – used to display differences in files by comparing line by line.
20. uptime – displays the system uptime as well as the load average.
21. top – shows a real-time view of running processes in Linux.
22. vmstat – used to obtain information about memory, system processes, paging, interrupts, block I/O, disk, and CPU scheduling.
23. htop – a process viewer and manager that is interactive.
24. dstat – allows you to view all of your system resources instantly. All-in-one vmstat, iostat, netstat, and ifstat utility.
25.. Iftop is a network traffic viewer.
26. nethogs – is a network traffic analyzer.
27. iotop – is an interactive I/O viewer. Get a snapshot of storage r/w activity.
28. iostat – provides statistics on storage I/O.
29. netstat -used to show network statistics.
30. ss – ss command is a simpler and faster version of the now obsolete netstat command.
31. ls -al – List all files and directories including, hidden files and other information like permissions, size and owner.
32. ssh – secure protocol used as the primary means of connecting to Linux servers remotely.
33. sudo – run commands with administrative privileges.
34. cd – navigate between directories.
35. pwd – displays the current directory path.
36. cp – copy files and directories.
37. mv – move file or directories.
38. rm – deletes files and directories.
39. mkdir – create new directories.
40. touch – used to create, update a computer file or directory’s access and modification dates.
41. man – used to read system reference manuals.
42. apropos – searches manual page names and descriptions for a user-supplied keyword.
43. rsync – remote file transfer and synchronization.
44. tar – is an archive utility.
45. gzip – use for compression and decompression of files.
46. b2zip – a compression utility comparable to gzip. It employs a distinct compression algorithm.
47. zip – used for file packaging and compression (archiving).
48. locate – in Linux, search for files.
49. ps – allows you to list the status of processes running on your system easily.
50. cron – execute scheduled tasks.
51. nmcli – sused to display network device status, create, edit, activate/deactivate, and delete network connections.
52. ping – sends an ICMP ECHO REQUEST to network hosts.
53. traceroute – examine the path packets follow to reach a specific host.
54. mtr – is a network diagnostic tool, a combination of ping and traceroute commands.
55. nslookup – interactively query Internet name servers (NS).
56. host –used for DNS (Domain Name System) lookup operations.
57. dig – DNS lookup tool.
58. wget – download files through HTTP, HTTPS, FTP, and FTPS.
59. curl – data transport via several network protocols. (Can handle more protocols than wget)
60. dd – used to convert and copy files.
61. fdisk – Modify the disk partition table.
62. parted – used to create and manipulate partition tables.
63. blkid – a command-line utility for finding and printing block device attributes.
64. mkfs – create a Linux file system.
65. fsck – a utility for determining the consistency of a file system.
66. nc – used for just about anything under the sun involving TCP or UDP.
67. umask – returns, or sets, the value of the system’s file mode creation mask.
68. chmod – alters the access rights of file system objects.
69. chown – alter the owner and group of a file.
70. chroot – used to change the root directory.
71. useradd – create a new user or alter the default information for a new user.
72. userdel – used to delete a user account and all associated files.
73. usermod – used to edit or change any existing user account’s properties.
74. vi is a text editor.
75. cat – displays the contents of a file.
76. tac – reverse output file contents.
77. more – show file contents one screen/page at a time.
78. less – identical to more, but with more features
79. tail – used to show the last few lines of a text file or piped data.
80. head – used to show the first few lines of a text file or piped data.
81. dmesg – displays the kernel ring’s message buffer.
82. journalctl – Tused to view systemd, kernel and journal logs.
83. kill – terminates a process.
84. killall – sends a kill signal to all instances of a specific process.
85. sleep – pauses program execution for a given amount of time.
86. wait – suspend script execution until all background jobs have been completed.
87. nohup – short for no hang up is a command in Linux systems that keep processes running even after exiting the shell or terminal.
88. screen – keep a remote server session open. (It also functions as a full-screen window manager.)
89. tmux is a terminal multiplexer.
90. passwd — Change the password of a user.
91. clear – clears the terminal’s screen.
92. env – run a command in an altered environment.
93. systemctl – used to control and manage systemd and services.
94. hostnamectl – Get system information including, operating system, kernel, and release version.
95. date – Display the current system date and time.
96. hostname – Display the hostname of the system.
97. ifconfig – Display the IP and Mac Address of the system.
98. ip addr show – List all IP addresses and network interfaces.
99. ip addr add IP-Address dev eth1 – Add a temporary IP address to interface eth1
100. netstat -pnltu – Display all listening ports.
101. whois {domainname} – Display more information about any domain.
102. dig {domainname} – Display DNS information of any domain.
103. host {domainname} – Perform an IP lookup for a domain.
104. dig -x {IP-Address} – Perform a reverse lookup of an IP address.
105. dig -x {domainname} – Perform a reverse lookup on a domain.
106. ping host-ip – Check connectivity between two hosts.\
107. lsof – List all files opened by running processes.
108. bg – Display stopped or background jobs.
109. pidof – Gives the Process ID (PID) of a process.
110. tcpdump – analyze network traffic.
111. echo – The echo command is used to display a line of text to the standard output(stdout).
112. printf – The printf command is used to format and print data to the standard output.
113. batcat – Modern version of cat command with syntax highlighting.
114. paste – the paste command, like the cat command, merges lines in a file into a single large single line.
115. crontab – Used to manage cron jobs in Linux.
116. whoami – Prints the username of the user logged in.
117. service – To perform tasks on different services.
118. mount – Find files on system by name.
119. pmap – To show the memory map of a process.
120. users – The usernames of users.