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Typography

Logo Design

Illustrator Path Basics

Unity

Unity is the underlying principle that summarizes all of the principles and elements of design. It refers to the coherence of the whole, the sense that all of the parts are working together to achieve a common result; a harmony of all the parts.

Unity can be achieved through the effective and consistent use of any of the elements, but pattern-- that is, underlying structure-- is the most fundamental element for a strong sense of unity. Consistency of form and color are also powerful tools that can pull a composition together.

Josef Koudelka Portugal 1976
However, unity also exists in variety. It is not necessary for all of the elements to be identical in form providing they have a common quality of meaning or style. For example, fashions from a specific period share common features of silhouette, materials, and color that identify the style of the day, or the look of a particular designer.

Unity can also be a matter of concept. The elements and principles can be selected to support the intended function of the designed object; the purpose of the object unifies the design.

Conceptual Models and Mental Models

The designer analyzes the content to be taught, the task to be performed or the information to be displayed, and defines its structure and functionality. This structure in the designer's mind is called a conceptual model.

The user also has a model, a mental model which he has built up according to his experiences in a site. For example, a designer may have in mind an online catalogue, with feature screens describing products and an online ordering system (here again, we use the metaphor of the catalogue to make things easier to understand). The user may be familiar with the paper version of a catalogue but may be unsure how the online version corresponds to his understanding. After trying options, the user will begin to develop his own mental map, based on his experiences. However, if his mental model is different from the designer's conceptual model, errors will occur and the user will become confused or frustrated. In designing a conceptual model, the closer your design matches familiar situations, the easier your system will be to use