11/21/2017 - 1:06 AM

powershell + cmd

* examples in this color or italized lightgray or maybe in silver

`start`   start a program / command / batch script (opens in a new window)
  `start .`     open current directory in Explorer  

  get-childitem *.mp3 | foreach { rename-item $\_ $\"old part", "new part") }   rename all `mp3` files, changing `old part` to `new part`  
  `$i = 1`
  get-childitem * | %{ rename-item $\_ -newname ('{0:D1}.jpg' -f $i++) }
  rename all files as sequential numbers, starting from `1.jpg`;
  using `{0:D2}` instead of `{0:D1}` adds leading zero to single numbers: `01.jpg`