This is helps as visual of what Fitt's Law is.

Fitt's Law in HCI Visual

Larger Objects -> Faster Pointing
Shorter Distances -> Faster Reactions

Fitt's Law Implications

An idea that tells us how long it will take to move a pointer from a position to hit a target

University of Michigan - Ann Arbor

The movement is inescapable in human-computer interaction (HCI). This is an important concept for user interaction with devices. Motor movements include: Typing, Pointing, Clicking, Dragging, Drawing, Pinching 

Motor Behavior

MacKenzie, I. S. (2003). Motor behaviour models for human-computer interaction. In J. M. Carroll (Ed.) HCI models, theories, and frameworks: Toward a multidisciplinary science, pp. 27-54. San Francisco: Morgan Kaufmann.

Motor Behavior Reference

Simple idea that the more choices you present users with, the longer it will take them to make a choice.

Hick's Law in HCI

Fitt's Law in HCI

Predicts the time needed to steer a pointer such as a mouse
cursor or a finger on a touch device, from one end to the
other as quickly as possible.

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