The text consistency, explains the four main types of design consistency. The four main types of consistency are, Aesthetic, Functional, Internal and External. “Consistency enables people to efficiently transfer knowledge to new contexts, learn new things quickly, and focus attention on the relevant aspects of a task.” (Lidwell, Holden & Butler (2003). Aesthetic consistence refers to the consistency of style and appearance to a product, aesthetic consistency enhances recognition to others on what particular product may be, it communicates membership and sets emotional expectations. Functional consistency is meaning and action. “It improves usability and learnability by enabling people to leverage existing knowledge about how the design functions.” (Lidwell, Holden, & Butler, 2003). An example used in the text that has been provided to describe functional consistency is a remote control., “Videocassette recorder control symbols to MP3 music players, the consistent use of these symbols on new devises enables people to leverage existing knowledge. (Lidwell, Holden & Butler (2003). The consistency of functional use in the design of these types of products enables the user to rely on pre-existing knowledge of how each function works, it also creating a product knowledge level with ease as it the consumer is already familiar with each of the settings works. The Next type of consistency is internal. Internal consistency is an indicator that cultivates trust in people, the example displayed in the text was in relation to park signage, this is a excellent example as passers by learn from observing signs in the park and then can relate them to others they may see, this is internal consistency as the sign is internally imprinted into you. The last main types of design consistency is external, external consistency is consistency with other the other design consistency component’s in different settings. Although one of the most unique design types can be the most difficult to achieve as it cannot be linked with any other external design types.