pi@raspberrypi ~ $ ls
Desktop  Documents  ocr_pi.png  python_games  Scratch
pi@raspberrypi ~ $ pwd
/home/pi
pi@raspberrypi ~ $ ls ..
pi
pi@raspberrypi ~ $ ls /
bin   dev  home  lost+found  mnt  proc  run   selinux  sys  usr
boot  etc  lib   media       opt  root  sbin  srv      tmp  var
pi@raspberrypi ~ $ cd Documents/
pi@raspberrypi ~/Documents $ ls
Scratch Projects
pi@raspberrypi ~/Documents $ mkdir Python\ Projects/
pi@raspberrypi ~/Documents $ ls
Python Projects  Scratch Projects
pi@raspberrypi ~/Documents $ cd Python\ Projects/
pi@raspberrypi ~/Documents/Python Projects $ ls
pi@raspberrypi ~/Documents/Python Projects $ nano test.txt
pi@raspberrypi ~/Documents/Python Projects $ ls
test.txt
pi@raspberrypi ~/Documents/Python Projects $ rm test.txt 
pi@raspberrypi ~/Documents/Python Projects $ nano test.txt
pi@raspberrypi ~/Documents/Python Projects $ ls
test.txt
pi@raspberrypi ~/Documents/Python Projects $