At the end of lecture 1, your instructor typed "history > lec1hist"
into the shell.  He then opened lec1hist in the emacs editor and
deleted lines corresponding to earlier seesions.  Then he wrote this
paragraph, saved the file, and put the result on the website.  history
is a special "builtin" for the shell; I encourage you to learn more
about it.  
  244  tcsh
  245  pwd
  246  ls
  247  ls old
  248  ls /
  249  cd /
  250  pwd
  251  ls
  252  ls /homes/iws/djg
  253  ls old
  254  pwd
  255  cd /homes/iws/djg
  256  cd /
  257  cd homes/iwd/djg
  258  cd homes/iws/djg
  259  cd /
  260  cd ~
  261  cd /
  262  cd
  263  touch foo
  264  ls
  265  mkdir bar
  266  ls
  267  cd bar
  268  ls
  269  echo "hellow world\!"
  270  echo "hi"
  271  echo "hi" > someFile
  272  ls
  273  cat someFile
  274  emacs &
  275  ls
  276  cat anotherFile 
  277  clear
  278  mv
  279  cp
  280  rm
  281  man cp
  282  history > lec1hist