The GNU Core Utilities package includes over 100 basic programs that are expected to exist on all Linux systems. They are often used by scripts, other programs and each other.

arch/binhardware name (uname -m)
base64/usr/binencode or decode
basename/binstrip directory components
chgrp/binchange group
chmod/binchange mode
chown/binchange owner and/or group
chroot/usr/sbinrun command with new root directory
cksum/usr/binCRC checksum and byte count
comm/usr/bincompare sorted files line by line
cp/bincopy files and directories
csplit/usr/binoutput pieces of a file
cut/binoutput selected parts of lines
date/binoutput or set system date and time
dd/bincopy, convert and format
df/binoutput file system information
dir/usr/binlist file information (ls -Cb)
dircolors/usr/binset ls colours
dirname/usr/binstrip basename component
du/usr/bindisk usage
echo/binoutput (printf "%b\n$*")
env/binoutput or set environment variables
expand/usr/binconvert tabs to spaces
expr/binevaluate expressions
factor/usr/binoutput prime factors of integers
false/bindo nothing, unsuccessfully
fmt/usr/binreformat text
fold/usr/binwrap text
groups/usr/binoutput group memberships for users
head/usr/binoutput the first part
hostid/usr/binoutput hex identifier
hostname/binoutput or set hostname, domain, ip address
id/binoutput user and group information for user
install/usr/bincopy files and set attributes
join/usr/binjoin sorted files
kill/binterminate a process
link/binmake hard link
ln/binmake hard or symbolic link
logname/usr/binreturn the user's login name
ls/binlist file information
md5sum/usr/bincompute/check 128-bit MD5 digest
mkdir/bincreate directories
mkfifo/usr/bincreate FIFOs (named pipes)
mknod/bincreate block, FIFO or character special files
mktemp/binmake unique temporary files
mv/binmove and/or rename
nice/binrun with modified process scheduling
nl/usr/binoutput with line numbers
nohup/usr/binrun ignoring hangup signals
nproc/usr/binoutput available processors
numfmt/usr/binreformat numbers
od/usr/bindump files in various formats
paste/usr/binmerge corresponding or subsequent lines
pathchk/usr/bindiagnose invalid or unportable file names
pr/usr/binpaginate or columnate
printenv/usr/binoutput environment variables (env)
printf/usr/binprint formatted
ptx/usr/binpermuted index
pwd/binprint working directory
readlink/usr/binoutput value of a symlink
realpath/usr/binoutput resolved absolute file name
rm/binremove files (unlink) or directories
rmdir/binremove empty directories
seq/usr/binoutput numeric sequences
sha1sum/usr/bincompute/check 160-bit SHA digest
sha224sum/usr/bincompute/check 224-bit SHA digest
sha256sum/usr/bincompute/check 256-bit SHA digest
sha384sum/usr/bincompute/check 384-bit SHA digest
sha512sum/usr/bincompute/check 512-bit SHA digest
shred/usr/binoverwrite files
shuf/usr/binoutput random permutation (shuffle)
sort/binsort, merge or compare
split/usr/binsplit files
stat/binreport file or file system status
stdbuf/usr/binrun with modified I/O stream
stty/binoutput or change terminal characteristics
sum/usr/bincompute 16-bit checksum
sync/binforce cached disk writes
tac/binconcatenate in reverse
tail/usr/binoutput the last part
tee/usr/bincopy/redirect output
test/usr/binevaluate expressions
timeout/usr/binrun with a time limit
touch/binchange timestamps
tr/usr/bintranslate, squeeze and/or delete
true/bindo nothing, successfully
truncate/usr/binshrink or extend the size of files
tsort/usr/bintopological sort
tty/usr/binoutput terminal device
uname/binoutput system information
unexpand/usr/binconvert spaces to tabs
uniq/usr/binfilter adjacent matching lines
unlink/binremove a file (rm)
uptime/usr/binsystem uptime and load
users/usr/binoutput who is currently logged in
vdir/usr/binlist file information (ls -lb)
wc/usr/bincount bytes, characters, words, lines
who/usr/binverbose output of who is currently logged in
whoami/usr/bineffective user id
yes/usr/binrepeatedly print a string until interrupted