| ls | list files and directories in the current directory |
| cd | change directory |
| pwd | print working directory |
| mkdir | create a new directory |
| rm | remove a file or directory |
| cp | copy a file or directory |
| mv | move or rename a file or directory |
| cat | display the contents of a file |
| chmod | changes the permissions of a file or directory |
| lsblk | lists all available block devices (such as hard drives and USB drives) |
| df | displays the amount of disk space used and available on the file system |
| top | displays a list of running processes and system resource usage |
| history | displays a list of previously executed commands |
| kill | terminates a process by ID or name |
| touch | creates an empty file or updates the timestamp of an existing file |
| grep | search for a specific pattern in a file Syntax: grep [pattern] [filename] Example: grep “error” logfile.txt |
| sudo | execute a command with superuser privileges |
| sudo su | switches to the root user account |
| man | displays the manual pages for a command |
| head | displays the first few lines of a file |
| tail | displays the last few lines of a file |
| apt-get | command-line tool used to manage software packages in Debian-based Linux distributions |
| ssh | secure shell client used to remotely connect to a server |
| scp | secure copy used to transfer files between two computers securely |
| ps | displays information about the running processes |
| uname | displays the name and version of the current operating system |
| crontab | used to schedule tasks to run automatically at specific times |