OS X Yosemite: Create and use aliases
To make it easier to find a file, folder, app, or disk, you can create an alias for it and put the alias in an easy-to-find location. When you open an alias, the original item opens.
Create an alias
Select the item, then choose File > Make Alias, or press Command (⌘)–L.
You can create as many aliases for an item as you want, then drag them to other folders or to the desktop.
To create an alias and move it in one step, press Option-Command (⌘) while you drag the original item to another folder or to the desktop.
Add an alias to the Finder sidebar or Dock
The items you see in the Finder sidebar and the Dock are aliases. For example, in the sidebar, Documents is an alias for the Documents folder located inside your home folder. You can add your own aliases to the sidebar or the Dock.
Add a folder, app, or disk alias to the Finder sidebar: Drag the original item to the Favorites section.
Add an app or individual file to the Finder sidebar: Hold down the Command (⌘) key and drag the original item over the Favorites section title.
Add a file, folder, or app alias to the Dock: Drag the original item to the Dock.
Drag files and folders to the right of the Dock’s separator, and apps to the left. If you moved the Dock to the side of your desktop, drag files and folders below the separator, and apps above.
Remove an alias from the Finder sidebar or Dock
Drag the item out of the sidebar or Dock until you see Remove.
If you remove an item from the sidebar or Dock, only the alias is removed. The original item isn’t removed from your Mac.
Find the original item for an alias
Select the alias, then choose File > Show Original, or press Command (⌘)–R.