VISUALLY PERCEIVED AREA CREATED BY AN ENCLOSING LINE

PREDICTABLE EDGES THAT APPEAR TO HAVE A MACHINE-MADE QUALITY

CONSISTS OF NATURAL, CURVING, UNPREDICTABLE EDGES

HAVE DISTINCT EDGES CREATED BY ABRUPT CHANGES IN COLOR, VALUE, PATTERN, OR TEXURE

CREATED BY GRADUAL/INDISTINCT CHANGES IN PATTERN