Concepts inAn empirical comparison of pie vs. linear menus
Menu (computing)
In computing and telecommunications, a menu is a list of options or commands presented to an operator by a computer or communications system. A menu is used in contrast to a command-line interface, where instructions to the computer are given in the form of commands.
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Pie
A pie is a baked dish which is usually made of a pastry dough casing that covers or completely contains a filling of various sweet or savoury ingredients. Pies are defined by their crusts. A filled pie (also single-crust or bottom-crust), has pastry lining the baking dish, and the filling is placed on top of the pastry, but left open.
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Pie menu
In computer interface design, a pie menu (also known as a radial menu) is a circular context menu where selection depends on direction. A pie menu is made of several "pie slices" around an inactive center and works best with stylus input, and well with a mouse. Pie slices are drawn with a hole in the middle for an easy way to exit the menu. Pie menus work well with keyboard acceleration, particularly four and eight item menus, on the cursor keys and the number pad.
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Radius
In classical geometry, a radius of a circle or sphere is any line segment from its center to its perimeter. By extension, the radius of a circle or sphere is the length of any such segment, which is half the diameter. If the object does not have an obvious center, the term may refer to its circumradius, the radius of its circumscribed circle or circumscribed sphere.
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Fitts's law
Fitts' law (often cited as Fitts's law) is a model of human movement primarily used in human¿computer interaction and ergonomics that predicts that the time required to rapidly move to a target area is a function of the distance to the target and the size of the target. Fitts's law is used to model the act of pointing, either by physically touching an object with a hand or finger, or virtually, by pointing to an object on a computer monitor using a pointing device.
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Circumference
The circumference is the distance around a closed curve. Circumference is a special perimeter.
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Circle
A circle is a simple shape of Euclidean geometry consisting of those points in a plane that are equidistant from a given point, the centre. The distance between any of the points and the centre is called the radius. Circles are simple closed curves which divide the plane into two regions: an interior and an exterior.
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