Contrast creates emphasis by differentiating a design object from its visual or semantic context. Contrast can be established by changing one or more of a design object's object-level aspects. For example, an emphasized word may be bold (which is a shift in font) or a different size or color. (Notice that linked terms on this website use multiple color contrasts: blue for unvisited links and purple for visited links.)

Contrast is closely linked with its obverse consistency. Contrast's effect derives from a design object's differentiation from consistent parameters. Contrasted design objects such as emphasized words may in fact form their own shared consistency; for example, it is common for all emphasized words in a document to use the same shifted font, color, or size parameters, thereby signifying their shared classification. This is a further demonstration of the necessary association between these two complementary design principles.