pwd--> Print current working directory.
ls--> List files in the current directory.
cd--> change directory.
mkdir--> Create a new directory.
touch--> Create an empty file
cp--> Copy files or directory.
mv--> Move or rename files or directories.
cat--> Display the content of a file.
man--> Display the manual for a commands.
echo--> Print text to the terminal.
chmod--> Change the permissions.
chown--> Change file ownership.
ps--> Display currently running processes.
kill--> Terminate a process.
grep--> Search for a pattern in files.
find--> Search for files and directories.
tar--> Create or extract tar archives.
gzip--> Compress or decompress files.
df--> Display disk space usage.
du--> Display file and directory space usage.
ifconfig--> Display network interface information.
ping--> Tast network connectivity.
ssh--> Connect to a remote server ( secured shell )
scp--> Copy file over SSH ( secured copy shell )
wget--> Download files from the internet.
top--> Display real-time system statistice.
history--> Display commands history.
nano--> Simple text editor.
clear--> Clear the terminal screen.
df--> Display disk space usage.
date--> Display or set the system date and time.
cal--> Display a calendar.
uname--> Display system information.
head--> Display the beginning of a file.
tail--> Display the end of a file.
wc--> Count lines, words, and characters in a file.
sort--> Sort lines of text files.
whoami--> Display the current username.
pwd--> Print current working directory.
file--> Determine file type.
alias--> Create commands history.
uptime--> Display system uptime.
ls -l--> List files with detailed information.
mkdir -p--> Create Parent directory as nested.
rmdir--> Remove an empty directory.
passwd--> Change user password.
reboot--> Reboot the system.
ls option_flag arguments --> list the sub directories and files avaiable in the present directory
ls -a --> list all including hidden files and directory
ls *.sh --> list all the files having .sh extension.
ls -i --> list the files and directories with index numbers inodes
ls -d */ --> list only directories.(we can also specify a pattern)
cd path_to_directory --> change directory to the provided path
cd ~ or just cd --> change directory to the home directory
cd - --> Go to the last working directory.
cd .. --> change directory to one step back.
cd ../.. --> Change directory to 2 levels back.
mkdir directoryName --> to make a directory in a specific location.
