How do you open a folder in OSX using the keyboard?

You can use Command+Down Arrow to open a folder.

  • Command+Up Arrow will take you to the parent folder.
  • Command+Right Arrow or just Right Arrow will expand (toggle the triangle chic) the folder.
  • Command+Left Arrow or just Left Arrow will retract the folder.

Also good to know is Command + any of 1, 2, 3 or 4 will toggle between the different view types (icon, list, columns, cover flow respectively).