I’m taking notes on ranking the usefulness of all GNU Core Utils provided in this video, see also List of GNU Core Utilities commands, and GNU Core Utils Manual. They exist in almost all Linux distributions, acually they are part of your linux system! (becasue Linux = Linux Kernel + GNU Utils)
I also changed his ranking a bit based on my ideas!
Another change is that, some very important very basic command-line utils, although not part of core utils, were also added here because of their importance and usefulness. They are cd, grep, find, sed, awk, tar, sudo and fzf. Non basic command-line utils like yazi or ranger can also be very useful but they should be put into a separate page.
Tip: If you want to learn about a command listed here, for example grep, try one of the commands for a manual:
man grep # Open a complete manual for grep
tldr grep # Short prompts and examples for using grepYou will need to install man or tldr to see the manual.
cat prints or concats the content of files.
cd changes directory.
chmod is used to change permissions of files or directories.
chown is used to change the owner of files or directories.
cp is used to copy.
echo prints text
env run a program in a modified enviroment.
groups command prints a list of groups that a user belongs to.
kill is used to send signal or terminate a process.
ln is used to create links.
ls list files in a directory.
mkdir is used to create directory, absolutely useful.
mv is used to move or rename a file.
pwd command prints the current working directory.
rm removes file or directories.
su switches user or root.
sudo run as root.
touch creates an empty file, or update the atime of an existing file.
grep can be used to search text.
find can be used to search files.
fzf can be used to search files or make option menus. Unlike other tools in this list, it is not part of GNU Core utils or shell command line default tools, and is usually not installed by default.
basename strips directory and suffix from filenames.
chroot primitive form of containerization.
date command prints the current date.
dd convert and copy a file. It can deal with low level things, but is an a bit dangerous command.
df prints the disk info (free space).
dirname converts a file name to its directory name.
head prints the first few lines.
mktemp is used to create temporary files and directories.
nice command can be used to run command with a given priority level.
nohup runs a command immune to hangups with output to a non-tty. It is useful for running long running commands.
realpath is used to resolve a canonical absolute path of a file, including ambiguities like symlinks.
sleep is used to delay.
sort is used to sort lines in a file.
sync synchronize cached writes to persistent storage.
tail prints the last lines of a file.
tee sends output to file and prints at the same time.
timeout will be able to restrict the amount of time a command runs, avoiding stucking.
uniq counts the unique lines.
users prints the user names of users currently logged in.
wc counts the number of words or lines.
whoami prints the current user, frequently used in scripts.
b2sum is used to do checksums.
base32 does similar things with base64 and instead of 64, it does 32.
base64 can convert binary data into ascii encoding.
comm command can compare two sorted files line by line, or perform set operations on lines.
cut remove sections from each line of files, companion of paste.
du provides estimation on file space usage.
expr evaluate logical or mathematical expressions.
false is the opposite of true.
fmt is a text formatter.
fold wrap each input file to fit specified width.
install copies files and sets attributes.
join join lines of two files on a common field.
md5sum is used to do checksums.
mkfifo create named pipes (FIFOs) with the given names. It is a magical gate for inter process communication on your file system!
paste merges lines of files.
printf prints text in advanced formmating options.
rmdir is used to remove empty directory only, it is a safe alternative for rm.
sed for text editing
awk a text editing ‘programming language’
sha256sum is used to do checksums.
sha512sum is used to do checksums.
tr does character level replace, it translate or delete characters.
tar is used to manage tarballs.
true is placeholder for success return code.
uname is used to print your system informations.
uptime prints the live time since last boot.
[ is a synonym for test.
hostname prints the hostname.
id real effective user and group id.
nproc tells the number of cpus in your system. It may be useful to be used as an argument to a makefile.
od can be used to dump files in octal or other formats.
shuf command can be used to generate random test cases.
stty can be used to change advanced features of a terminal.
tty print the file name of the terminal connected to standard input.
readlink can be used to read symbolic links.
seq prints a sequence of numbers.
stdbuf
yes can be used in script to provide y for confirmations.
chcon changes the file security context.
chgrp changes group ownership of a file or directory. Note that chown already does the job.
dircolors can be used to configure the colors of files in your system.
factor is used to factor integers.
logname
mknod
numfmt is used to format numbers.
pathchk check whether file names are valid or portable.
sha1sum
stat display file or file system status.
tac concatenate and print files in reverse.
truncate shrinkes or expand to a file to the specific size.
who shows the list of users that are currently logged in. The author of the video gave it D-tier but I think in a multiuser system this can be quite useful, so I think it belongs to C-tier.
arch is used to print archetecture.
cksum is obsolete.
csplit split a file into sections determined by context lines.
dir
expand converts all tabs into spaces in a file. I think this may be useful for some programming languages. But typically it is not of much use.
hostid prints the numeric identifier for the current user. Not really useful.
link
pinky
pr
printenv
ptx
runcon is only used in SELinux.
sha224sum
sha384sum
shred command overwrites a file to hide its contents for better deletion.
sum
tsort
unexpend is the inverse of expand but it is not very stable.
unlink
vdir is almost just ls -l.