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).

More terms you might want to know

Negative Space

The unused or empty space in a composition of images, either two-dimensional (as with paintings) or three-dimensional (as with sculptures).

Typeface Design

The art and discipline of putting together set of typefaces into a harmonious and readable type system. A typeface designer spends much time considering many things such as clear visual message, readability at different sizes, legibility at small point sizes, ease of use for printing processes on its own or over the top of other fonts.

Interaction Design

The design of the interaction between users and products. Interaction design is focused on creating products that enable the user to achieve their objective(s) in the best way possible.


A non-functional first draft of a design.


A sample of the target audience for which a product or service is intended.

User Flow

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

Centre Aligned

A layout where all the content, mostly text, is aligned to the centre. The overall purpose of a Centre Alignment is to make it easier for users to read and scroll through content.

Complementary Colours

Colours that directly across the colour wheel, like blue and orange. When you put these colours next to each other, they make a great contrast together. Complementary colours are often found in nature.


All available space (line-height) between two consecutive lines of text; this measurement should be adjusted for either ascenders or descenders. In hand typesetting, leading referred to thin strips of lead inserted by hand between lines of type in the composing stick to increase vertical distance.


The art and technique of arranging type to make written language legible, readable, and appealing when displayed.


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