Spatial nature of KMS] Provides room for annotation. Empty space in a frame provides a handy place for peripheral items such as an author's note or a reviewer's comment about the contents of the frame. In KMS, creating such items is as simple as moving the cursor to an empty area in the frame and starting to type. As long as the note or comment is not unduly large, it can happily coexist with the other items in the frame.
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