Commands | Description |
---|
alias | Converts complex commands into simpler ones. |
bzip2 / bunzip2 | Compresses a file / Decompress a bzip2 file. |
bzcat / bzmore | Displays files compressed with bzip2. |
cal | Displays calendar. |
cat | It is a multi-function command. |
cd | Changes the current working directory. |
chage | Sets an expiration date for a user account. |
chgrp | Changes group. |
chmod | Changes permission for a file or directory. |
chown | Changes the owner of a file or directory. |
chsh | Changes the shell. |
clear | Clears the terminal. |
comm | Compares two streams or files. |
cp | Copies file content from one file to another file. |
cut | Used to display the desired column from a file. |
date | Displays the current date. |
df | Checks the disk space in the system. |
echo | Prints the typed word on the terminal. |
exit | Exits from the current user group to the last group. |
export | Exports shell variables to other shells. |
file | Displays the type of file. |
find | Finds files for a particular search. |
gpasswd | Transfers group membership to another user. |
grep | Filters lines of text containing a certain string. |
groupadd | Creates a group. |
groupdel | Permanently removes a group. |
groupmod | Changes group name. |
groups | Displays the group name to which the current user belongs to. |
gzip / gunzip | Compresses a file / Decompress a gzip file. |
head | Displays the first ten lines of a file. |
history | Displays older commands from the shell command history. |
HISTSIZE | Determines the number of commands to be stored in the current environment. |
HISTFILE | Displays the file that contains the history. |
HISTFILESIZE | Sets the number of commands kept in the history file. |
id | Tells about the user's id in the system. |
less | Displays file content according to the width of the terminal. |
locate | Searches a file in the database. |
ls | Lists all the files of a directory. |
man | Displays the manual page for the specified command. |
mkdir | Creates directory. |
more | Displays one output screen at a time. |
mv | Renames directories or files. |
od | Displays a file content in octal format. |
passwd | Set a password for a user group. |
pwd | Display the current working directory location. |
PS1 | Change the prompt name in the terminal. |
rename | Renames more than one file at once. |
rm | Removes a file. |
rmdir | Removes a directory. |
set -o noclobber | Prevents file from getting overwritten. |
set +o noclobber | Allows overwriting in the existing file. |
set -u | Displays undefined variables as an error. |
set +u | Displays nothing for an undefined variable. |
set -x | Displays shell expansion. |
set +x | Disables shell expansion. |
sed | Performs editing in streams. |
sleep | Waits for the specified number of seconds. |
sort | sorts the content in alphabetical order. |
su | It allows a user to run a shell as another user. |
sudo | It allows a user to start a program with the credentials of another user. |
tac | Displays file content in the opposite order. |
tail | Displays the last ten lines of a file. |
tar | Compresses a directory. |
tee | Puts stdin on stdout and then into a file. |
time | Displays time taken to execute a command. |
touch | It creates an empty file. |
tr | Translates characters. |
type | Displays information about command type. |
uniq | Sorts and display multi times repeating lines only once. |
unset | Removes a variable from a shell. |
useradd | Adds users. |
userdel | Deletes users. |
usermod | Modifies the properties of a user. |
vi | Opens vi editor to write a program. |
w | Displays who is logged on and what are they doing. |
wc | Counts words, lines, and characters. |
who | Tells who is logged on the system. |
whoami | Tells the name of the user. |
who am i | Displays the line pointing to your current session. |
zcat / zmore | Views the files compressed with gzip. |