Apple Compressor 3 - Manual (Page 18)

3 Drag source files from the Finder or the desktop to the Batch window.
Note: If you drag multiple files to the thumbnail area (with the arrow in this example),
only the last file is added to this job and all other files are ignored.
The thumbnail area
of the job
New jobs are created for each source file you dragged to the batch.
Each source file creates
a job in the batch.
Target area (empty in
this case) of a job
See About the Batch Window for more information about the controls in the Batch
window.
Stage 2: Assigning Settings and Destinations
You need to assign at least one setting to each source media file job before you can
submit the batch for processing, but you can also add multiple settings to the same job
to transcode multiple versions of the media file. Each setting-destination pair is known
in Compressor as a target.
18 Chapter 1 Getting Started Quickly