Merge directories in Mac OS X

You can quickly merge any two directories within Mac OS X by using the command line tool ditto. Launch the Terminal and use the following syntax:

ditto directory1 directory2

If a directory already exists at the destination (directory2) then the contents of the source (directory1) will be merged with the contents of the destination (destination2). So I want to merge pictures from “August 2010″ into “Summer 2010″ I will use:

ditto "August 2010" "Summer 2010"

The man page for ditto describes further:

In its first form, ditto copies one or more source files or directories
to a destination directory. If the destination directory does not exist
it will be created before the first source is copied. If the destination
directory already exists then the source directories are merged with the
previous contents of the destination.

If you’re not familiar with the command line, you may want to just use the GUI to perform this type of action.