# cut as fragments and retrive the second fragment
cut -f2 something.txt
# cut by delimiter , and retrive the first fragment
cut -d, -f1
# print deplicate files
md5 *.png | cut -d= -f2 | uniq -c | sort -nr | grep -v " 1"
# disable $, print verbatim
echo '$HOME'
# $ is working
echo "$HOME"
# the final word
command !$
# the final arguments
command !*
# patch on previous command
^original^replacement
# edit in vim mode
set -o vim
