Definition of Consistency:
- A harmonious uniformity or agreement among things or parts is called consistency.
- It is a kind of repeated actions, all having same characteristics.
- Using similar elements for achieving similar task.
- Systems are usable and learnable when similar concepts are expressed in similar ways.
Purpose of Consistency:
- Users will feel comfortable and usability is increased.
- Systems are usable and learnable when similar concepts are in similar way.
- Enables people to quickly transfer prior knowledge to new contexts and learn quickly.
- Focus on task instead of learning how it works every time they switch the content.
- Ease in using the product.
Types of Consistency:
- There are four types of consistency:
1. Aesthetic
2. Functional
3. Internal
4. External
1. Aesthetic Consistency:
- Elements should look in similar manner.
- Font styles, sizes, colors.
- Easy to use and understand.
Examples of Asethetic Consistency:
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Consistency in Brand
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| Consistency of Police Uniform |
|
2. Functional Consistency:
- Functionality of elements should be consistent.
- Usage of symbols for a purpose should be small all over the application.
- It increases Predictability.
Examples of Functional Consistency:
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| Consistency of Symbol |
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| Consistency of Color |
3. Internal Consistency:
- Combination of asethetic and functional consistency.
- It improves usibility and learnability of product.
Examples of Internal Consistency:
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| Consistency in Apple Stores |
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| Consistency in Domino's Stores |
4. External Consistency:
- External Consistency means having the same aesthetic design or performance across multiple systems.
Examples of External Consistency:
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Consistency of Unique logo
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Consistency in Transportation
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