Fitts' law

Fitts' law is an unusually successful and well-studied model. Experiments that reproduce Fitts' results, and/or demonstrate the applicability of Fitts' law in somewhat different situations, are not difficult to perform. The measured data in such experiments often fit a straight line with a correlation coefficient of 0.95 or higher, a sign that the model is very accurate. Although Fitts only published two articles on his law (Fitts 1954, Fitts and Peterson 1964), hundreds of subsequent studies related to it are in human-computer intera ...

See also:

Fitts' law, Fitts' law - The model, Fitts' law - Success and implications of Fitts' law, Fitts' law - Some mathematical details, Fitts' law - A derivation of Fitts' law

Read more here: » Fitts' law: Encyclopedia II - Fitts' law - Success and implications of Fitts' law

QWERTY (pronounced "kwerty" or "Q-werty") is the most common modern-day keyboard layout on most English language computer and typewriter keyboards. It takes its name from the first six letters seen in the keyboard's top row of letters. The QWERTY design was patented by Christopher Sholes in 1868 and sold to Remington in 1873, when it first appeared in typewriters. QWERTY - Purpose. Frequently-used pairs of letters were separated in an attempt to stop the typebars from intertwining and becoming stuck, thus f ...

Including:

• QWERTY - Purpose
• QWERTY - Languages other than English
• QWERTY - Alternative keyboard layouts
• QWERTY - Trivia

Read more here: » QWERTY: Encyclopedia - QWERTY

Hrair is a number too large to count. This term is from the fictional language Lapine used in Richard Adams's Watership Down. In this novel, a rabbit's hrair is greater than 4 whereas, for humans, hrair would be greater than 7 plus or minus 2. From a psychological perspective, hrair is the point where the person is overwhelmed by concepts or change. The interesting thing about a person reaching their hrair point is that we are not only unable to understand the ne ...

See also:

The Magical Number Seven Plus or Minus Two, The Magical Number Seven Plus or Minus Two - Hrair from Watership Down and applications within programming

Read more here: » The Magical Number Seven Plus or Minus Two: Encyclopedia II - The Magical Number Seven Plus or Minus Two - Hrair from Watership Down and applications within programming

GUIs that are not PUIs are most notably found in computer games, and advanced GUIs based on virtual reality are now frequently found in research. Many research groups in North America and Europe are currently working on the Zooming User Interface or ZUI, which is a logical advancement on the GUI, blending some 3D movement with 2D or "2 and a half D" vectorial objects. Some GUIs are designed for the rigorous requirements of vertical markets. These are known as "application specific GUIs." One example of such an application specific GUI ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - Types of GUIs

GUIs that are not PUIs are most notably found in computer games, and advanced GUIs based on virtual reality are now frequently found in research. Many research groups in North America and Europe are currently working on the Zooming User Interface or ZUI, which is a logical advancement on the GUI, blending some 3D movement with 2D or "2 and a half D" vectorial objects. Some GUIs are designed for the rigorous requirements of vertical markets. These are known as "application specific GUIs." One example of such an application specific GUI ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI, Graphical user interface - Outlook

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - Types of GUIs

Because modern keyboards do not suffer from the problems of older mechanical keyboards, the QWERTY layout's separation of frequently used letter pairs is no longer strictly necessary. Several alternative keyboard layouts, such as Dvorak Simplified Keyboard arrangement (designed by Drs. August Dvorak and William Dealey and patented in 1936), have been designed to increase a typist's speed and comfort, largely by moving the most common letters to the home row and maximizing hand alternation. The effectiveness of these layouts is disputed, but ...

See also:

QWERTY, QWERTY - Purpose, QWERTY - Languages other than English, QWERTY - Alternative keyboard layouts, QWERTY - Trivia

Read more here: » QWERTY: Encyclopedia II - QWERTY - Alternative keyboard layouts

GUIs that are not PUIs are most notably found in computer games, and advanced GUIs based on virtual reality are now frequently found in research. Many research groups in North America and Europe are currently working on the Zooming User Interface or ZUI, which is a logical advancement on the GUI, blending some 3D movement with 2D or "2 and a half D" vectorial objects. Some GUIs are designed for the rigorous requirements of vertical markets. These are known as "application specific GUIs." One example of such an application specific GUI ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI, Graphical user interface - 3D user interfaces, Graphical user interface - Humor

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - Types of GUIs

GUIs were introduced in reaction to the steep learning curve of Command Line Interfaces (CLI), text-based user interfaces requiring commands to be typed on the keyboard. Since the command words in CLIs are usually numerous and composable, very complicated operations can be invoked using a relatively short sequence of words and symbols. This leads to high levels of efficiency once the many commands are learned, but reaching this level can take a while because the command words aren't easily discoverable. WIMPs ("wi ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI, Graphical user interface - 3D user interfaces, Graphical user interface - Humor

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - GUI vs. CLI

Frequently-used pairs of letters were separated in an attempt to stop the typebars from intertwining and becoming stuck, thus forcing the typist to manually unstick the typebars and also frequently blotting the document. The home row (ASDFGHJKL) of the QWERTY layout is thought to be a remnant of the old alphabetical layout that QWERTY replaced. QWERTY also attempted to alternate keys between hands, allowing one hand to move into position while the other hand strikes home a key. This sped up both the original double-handed hunt-and-peck techn ...

See also:

QWERTY, QWERTY - Purpose, QWERTY - Languages other than English, QWERTY - Alternative keyboard layouts, QWERTY - Trivia

Read more here: » QWERTY: Encyclopedia II - QWERTY - Purpose

GUIs were introduced in reaction to the steep learning curve of Command Line Interfaces (CLI), text-based user interfaces requiring commands to be typed on the keyboard. Since the command words in CLIs are usually numerous and composable, very complicated operations can be invoked using a relatively short sequence of words and symbols. This leads to high levels of efficiency once the many commands are learned, but reaching this level can take a while because the command words aren't easily discoverable. WIMPs, on the other hand, present the user with numerous widgets that represent ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI, Graphical user interface - Outlook

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - GUI vs. CLI

GUIs were introduced in reaction to the steep learning curve of Command Line Interfaces (CLI), text-based user interfaces requiring commands to be typed on the keyboard. Since the command words in CLIs are usually numerous and composable, very complicated operations can be invoked using a relatively short sequence of words and symbols. This leads to high levels of efficiency once the many commands are learned, but reaching this level can take a while because the command words aren't easily discoverable. WIMPs ("wi ...

See also:

Graphical user interface, Graphical user interface - Types of GUIs, Graphical user interface - GUI vs. CLI

Read more here: » Graphical user interface: Encyclopedia II - Graphical user interface - GUI vs. CLI

In Windows, the default location for the taskbar is at the bottom of the screen, following Fitts' law, and from left to right it contains by default the Start menu, Quick Launch bar, Taskbar buttons and Notification area (popularly called the system tray[1]). The Start menu contains commands that can access programs, documents, and settings. These commands include Programs, Documents, Settings, Find, ...

See also:

Taskbar, Taskbar - Microsoft Windows, Taskbar - Other desktop environments, Taskbar - Notes

Read more here: » Taskbar: Encyclopedia II - Taskbar - Microsoft Windows

Pie menus are faster and more reliable to select from than linear menus due to several factors: the large size and proximity of menu items (see Fitts' law) selection depends on direction instead of distance, so that experienced users use muscle memory. Nested pie menus make it easy to choose from many items Pie menus also show available options, in contrast to invisible mouse gestures. Pie menus which delayed appearance until the mouse button is released reduce intrusiveness to the same level as mouse gestur ...

See also:

Pie menu, Pie menu - Advantages, Pie menu - Disadvantages, Pie menu - Usage, Pie menu - Implementations, Pie menu - Pie menu rarity

Read more here: » Pie menu: Encyclopedia II - Pie menu - Advantages

A pointing task involves moving a cursor inside a graphical object and pressing a button, whereas a goal-crossing task involves moving a cursor beyond a boundary of a targeted graphical object. Goal crossing has been little investigated, despite sometimes being used on today's interfaces (e.g., mouse-over effects, hierarchical menus navigation and auto-retractable taskbars). Still, several advantages of crossing over pointing have been identified: Elongated objects such as hyperlinks are faster to cross than ...

See also:

Crossing Based Interfaces, Crossing Based Interfaces - Goal-Crossing Tasks, Crossing Based Interfaces - Laws of Crossing

Read more here: » Crossing Based Interfaces: Encyclopedia II - Crossing Based Interfaces - Goal-Crossing Tasks

This derivation is only meant as a high level sketch. It lacks the illustrations of, and may differ in detail from, the derivation given by Accot and Zhai (1997). Assume that the time required for goal passing (i.e. passing a pointer through a goal at distance A and of width W, oriented perpendicular to the axis of motion) can be modeled with this form of Fitts' law: Then, a straight tunnel of length A and constant width W can be approximated as a sequence of N evenly spac ...

See also:

Accot-Zhai steering law, Accot-Zhai steering law - Derivation of the model

Read more here: » Accot-Zhai steering law: Encyclopedia II - Accot-Zhai steering law - Derivation of the model

A common example is dragging an icon on a virtual desktop to a special trashcan icon to delete a file. Further examples include: Dragging a data file onto a program icon or special window for viewing or processing, Moving or copying files to a new location/directory/folder, Adding objects to a list of objects to be processed, Rearranging widgets in a graphical user interface to customize their layout, Dragging a command onto an object to which the command is to be applied, e.g. ...

See also:

Drag-and-drop, Drag-and-drop - Actions, Drag-and-drop - Examples, Drag-and-drop - Footnotes

Read more here: » Drag-and-drop: Encyclopedia II - Drag-and-drop - Examples

Windows is not the only operating system with a taskbar: similar bars are present in various Linux desktop environments. Mac OS X's Dock is also a kind of taskbar. In various KDE distributions, the taskbar is run by the kpanel program, and consists of two parts: the panel and the taskbar. The panel is a control bar across the bottom of the screen, which is used to find and launch applications and navigate among windows and desktops. It contains the menu, which is comparable to the Windows start menu; the disk navigator, ...

See also:

Taskbar, Taskbar - Microsoft Windows, Taskbar - Other desktop environments, Taskbar - Notes

Read more here: » Taskbar: Encyclopedia II - Taskbar - Other desktop environments

Beginner: click and release mouse button, causing the pie menu to display move the mouse into the desired slice click the desired action Exit by clicking the center. Expert (rely on muscle memory): click and hold down the mouse button move mouse onto the desired action release mouse button ...

See also:

Pie menu, Pie menu - Advantages, Pie menu - Disadvantages, Pie menu - Usage, Pie menu - Implementations, Pie menu - Pie menu rarity

Read more here: » Pie menu: Encyclopedia II - Pie menu - Usage

The logarithm in Fitts' law is called the index of difficulty ID for the target, and has units of bits. We can rewrite the law as T = a + bID Thus, the units for b are time/bit, e.g. milliseconds/bit. The constant a can be thought of as incorporating reaction time and/or the time required to click a button. The values for a and b change as the conditions under which pointing is done are changed. For example, a mouse and stylus may both be used for pointing, but have differe ...

See also:

Fitts' law, Fitts' law - The model, Fitts' law - Success and implications of Fitts' law, Fitts' law - Some mathematical details, Fitts' law - A derivation of Fitts' law

Read more here: » Fitts' law: Encyclopedia II - Fitts' law - Some mathematical details

Mathematically, Fitts' law has been formulated in several different ways. One common form is the Shannon formulation (proposed by Scott MacKenzie, and named for its resemblance to the Shannon-Hartley theorem) for movement along a single dimension: where T is the average time taken to complete the movement. (Traditionally, researchers have used the symbol MT for this, to mean movement time.) a and b are empirical constants, and can be determined by fitting a ...

See also:

Fitts' law, Fitts' law - The model, Fitts' law - Success and implications of Fitts' law, Fitts' law - Some mathematical details, Fitts' law - A derivation of Fitts' law

Read more here: » Fitts' law: Encyclopedia II - Fitts' law - The model