Wireframes allow for the development of variations of a layout to maintain design consistency throughout the site. This is an important part of the initial development stage because it creates user expectations and helps develop familiarity with the site.
OmniGraffle Wireframe Stencils
This is a set of shapes for making wireframes (low-fidelity web page schematics) in OmniGraffle version 5.x (Mac OS X). It consists of most of the basic elements you'll need to create user interface specifications. The screenshots below show all of the stencils in this set.
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