Just about every Mac user knows how to select a single file in the OS X Finder, but I’ve encountered many users who are perplexed by multiple file selection. Most of the confusion comes down to not knowing the primary methods of choosing groups of files, and that’s what we’ll aim to clear up here by focusing on the primary means of choosing groups of files: the click and drag, the shift click, command clicking, and using select all. Each are slightly different, but are all useful for moving files around within the Finder file system or even sending elsewhere to another Mac or iOS device.
Each of these tricks work to select groups of files in any Finder list view, be it icon, list, columns, or Cover Flow.
Select Contiguous Group of Files with Click+Drag or Shift+Click
Multiple files can be easily selected in OS X using the Click+Drag, which works just as it sounds; click and continue to hold the click while you drag within a window to draw a selection box and select more files.
Another option is to use the Shift+Click, which also works to select groups of contiguous files in the OS X Finder. Select the first file, hold down the Shift key, then click the last file, and you will instantly select all files between those two files as well.
Both of these methods work with files that are listed contiguously (that is, alongside one another in any view), but do not work if you’re looking to select files that are not grouped directly together. That’s when you’ll want to use Command+Click instead.
Select Multiple Nonadjacent Files with Command+Click
Command+Click lets you select multiple files that are not alongside each other in a Finder view. This can be as varied as necessary, whether that’s every other file, or one file at the very top of a list view and another two files at the very bottom, or any other variety in between.
You can scroll through a Finder window and select more items as you go down, just remember to hold down the Command key when selecting a new file(s).
Command+Clicking can also work to subtract and unselect files that have already been selected. For example, you could use Command+A to select all, or a Shift+Click to select a large group of files, then use Command+Click to precisely deselect a few files you don’t want actively selected in the group.
Select All Files in a Window with Command+A
Select All is fairly self explanatory, it selects everything in a given Finder window, and is just a matter of hitting Command+A, the Select All keyboard shortcut.
This has been around for a very long time, and other than the drawing rectangle, it’s probably the most widely known trick to work with groups of files. For those who aren’t fans of the keyboard shortcuts, you can also select every file in a window by pulling down the Edit menu and choosing “Select All”.
As mentioned in the prior trick, using Select All in conjunction with Command+Clicking to deselect things you don’t want is very helpful.
Finally, working with multiple files can be easier if the Finder Status Bar is enabled at all times, because it updates as files are selected, providing a live count of total documents selected. That, and more Finder tricks can be found here.