ls - list the files and directories in the current directory cd - change the current directory mkdir - create a new directory rmdir - remove a directory pwd - print the current working directory cp - copy files or directories mv - move or rename files or directories rm - remove files or directories touch - create a new empty file or update the timestamp of an existing file cat - concatenate and display files man - manual for a command htop - an interactive process viewer and system monitor chmod - change the permissions of a file or directory chown - change the owner of a file or directory tar - create or extract compressed archive files gzip - compress files gunzip - decompress compressed file ssh - connect to a remote server securely scp - securely copy files between systems ping - test network connectivity ifconfig - display or configure network interfaces netstat - display network connection information route - view or configure network routing tables top - display system resource usage and processes ps - display information about running processes kill - terminate a process systemctl - control system services and settings service - control system services useradd - add a new user to the system passwd - change the password for a user userdel - delete a user from the system su - switch user to become another user sudo - execute a command as another user or with elevated privileges uptime - display system uptime and load average df - display disk space usage du - display disk usage by file or directory mount - mount a file system umount - unmount a file system date - display or set the system date and time whoami - display the current user name which - locate a program or command in the system path finger - displays all the information about user uname - display system information history - display a list of previously executed commands echo - display text or variables to the console tee - redirect output to both a file and the console locate - locate any file on the system sort - sort lines of text in a file or input uniq - remove duplicate lines from a file or input head/tail - display the first/last few lines of a file or input