* cat - Concatenate and display file content
  * cd - Change directory
  * chmod - Modifies the permissions of a file or directory.
  * chown - Change file owner and group.
  * cp - Copies files or directories from one location to another.
  * curl or wget - Download files from the internet.
  * env - Prints environment or sets and executes command.
  * find - Search for files in a directory hierarchy. Searches for files and directories based on various criteria.
  * grep - Search for a pattern in files.
  * hostname - Sets or prints the name of current host system.
  * id - Returns users identity
  * ifconfig - The ifconfig utility is used to assign or to view an address to a network interface and/or configure network interface parameters.
  * ip - Ip is a utility to show or manipulate routing, network devices, interfaces and tunnels.
  * kill - Terminate a process. Sends a signal to a process, usually to terminate it.
  * ls - Lists files and directories in the current directory.
  * lsblk - Lists block devices.
  * lsof - Lists opened files.
  * lspci -  	Lists PCI devices.
  * lsusb - Lists USB devices.
  * mkdir - Make directory.
  * mv - Moves or renames files or directories.
  * netstat - Shows network status.
  * ps - Process status. Displays information about running processes.
  * pwd - Print working directory.
  * rm - Remove files or directories.
  * rmdir - Remove directory.
  * scp - Secure Copy. Copies files between hosts on a network using SSH.
  * ss - Another utility to investigate sockets.
  * ssh - Secure Shell
  * sudo - Execute a command with administrative privileges. Allows a permitted user to execute a command as the superuser or another user.
  * top or htop - Display system activity in real-time. Shows a dynamic view of system processes and resource usage.
  * touch - Creates an empty file or updates the access and modification times of a file.
  * uname - Prints basic information about the operating system name and system hardware.
  * who - Displays who is logged in.
  * whoami - Displays current username.