A file format that supports both static and animated images. It is a popular file format on the internet and social media due to its wide colour support, portability, and animating capabilities.

More terms you might want to know

Fitts' Law

A prediction model used in human-computer interaction. It states that the time required to move to a target area rapidly increases as the distance to the target increases. The law was proposed by Paul Fitts, an American psychologist, in 1954 as a mathematical model of movement with limited cognitive capacity.

Fitts hypothesized that one would quickly select its first apparent target when reaching for an object before considering alternatives — a phenomenon called "target fixation." This tendency would increase progressively with increased distance between the subject and object until it eventually became exponential (i.e., too far away).

User Interviews

The act of gathering qualitative data about a person's thoughts and feelings related to a product.


A unit of measurement that equals 1/6 of an inch, or 1/72 of a foot.

Design Sprint

A way to create and test designs. Designers use design sprints as a time-intensive method of quickly testing ideas and then pivoting into designing for user needs. A designer may then take the prototype they created on the first day of the design sprint and fix any usability issues with it, which is a quick way to get feedback on their work before continuing development.

Abstract Mark

An abstract mark is a type of logo where instead of being a recognizable object from everyday life, it is an abstract geometric form representing a business or brand. Famous examples include the BP starburst logo, and the Pepsi divided circle.

Bottom Navigation

One of the most common types of navigation in UI design. It's usually a system of one or more horizontal buttons placed at the bottom of the screen, directing users to other parts of an app or website. Bottom navigation is often used as an alternative to scrolling or tabbing through links on a page.

A/B Testing

A statistical method in which two variants of the same activity are compared against each other (typically with several variants), one at a time, and the most effective variant is selected.

Design Debt

A concept used in systems design to describe the negative consequences of making seemingly innocuous design changes. Shorthand for a product's delayed but inevitable need to be reworked due to earlier, seemingly trivial decisions not having been fully thought through in the original release.

Designers incur this "debt" by making quick and easy choices that save time in the present but cause more complex problems later on down the road when it becomes necessary to change or add something.

User Flow

The way that a user navigates through a website, app, etc.


A name, symbol or other distinctive feature that distinguishes one business's product from another's, often associated with a logo, design, slogan and other items.


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