ls -al; ls -al *.*; ls memo?.txt;
ls memo[0-9].txt; ls [A-Z]*.html
ls -al | less
ls -al; ls -al *.txt
ls -al *.html && rm *.html // only when successful
ls -al *.html || rm *.html // only when unsuccessful
cd ~/orchid
mv index.html index2.html
rmdir temp
pwd // present working directory
mkdir itis method
mkdir -p sas/stat policy/cba
rmdir temp
chown tiger list.txt
chmod a+rw *.html
chmod u=rw,g+x,o-wx *.html
chmod 644 *.html; chmod 711 *.php
rm *.bak
rm -rf temp
ln -s /usr/src/Linux/include/asm asm
alias a b
cat > memo.txt // write (Ctrl+D)
cat < memo.txt // display
cat memo1.txt memo2.txt //display
cat memo1.txt memo2.txt > memo3.txt //put them together
cat memo1.txt memo2.txt >> memo3.txt //append
more memo1.txt; less memo2.txt // display
file memo.txt // type of a file
echo $SHELL; echo $PATH; echo$PS1
find ~ -name "*.txt" | more
grep kucc625 ~/orchid
sort sorted.txt
wc index.html -lw // # line #word
fg; bg; kill
ps; ps aux;
du; df; free
command & //background
./install

mkfs // make file system
mount /dev/cdrom /mnt/cdrom
mount /dev/fd0 /mnt/fdd
umount /mnt/cdrom
fuser -km /mnt/cdrom // forcefully unmount
fdformat /dev/fdd; mke2fs /dev/fdd; mkdosfs /dev/fdd
mount /dev/cdrom /mnt/cdrom

gzip -cd Linux-2.2.02.tar.gz | tar xvf -
tar cf memo.tar memo1 memo2
tar xvzf Linux-2.2.02.tar.gz /z indicates automatic
bzip2 -cd Linux-2.2.02.tar.bz2 | tar  xvf -