Chapter+Six

In order to interact with a computer we need to be able to communicate with it and it with us. This is done by way of the user interface. We communicate with the user interface using one or more input devices, while the computer or interactive device communicates with us by way of an output device.
 * __Chapter 6 Technology 1: supporting single user interaction:__**

__**6.2 User interfaces:**__


 * command language is simply a set of words with an associated syntax.
 * back in the day we used to operate off of ms dos, which is still available in windows.
 * there were a defined set of words (commands) which a person could type in to receive a desired function.

__**6.3 Graphical user interfaces (GUIs)**__


 * WIMP stands for windows, icons, menu and pointer, though it is thought by some to have been a term of abuse used by computer scientists of end-users.
 * Window is a means of sharing a computer’s graphical display resources among multiple applications at the same time.
 * icon is an image or symbol used to represent a file, folder, application or device, such as a printer.
 * menu is a list of commands or options from which one can choose.
 * pointing devices most common example would be a mouse.
 * this form of interaction is called direct manipulation because we directly manipulate the on-screen objects.
 * the computer we use today is a direct manipulation interface, because we can use the mouse to make changes directly to the graphical user interface.

__**6.4 The major components of a GUI**__

Windows Menus Toolbars
 * -windows allow a workstation’s screen to be divided into rectangular areas which act like separate input and output channels that can be placed under the control of different applications.
 * users can see the output of several processes at the same time and choose which one will receive input by selecting its window, usually by lick on it with a mouse.
 * most applications running on personal computers are menu-driven.
 * menus should be grouped into menu topics, which are a list of menu items. Users select a command or option from the list, and an action is performed.
 * hierarchical menus are occasionally also called cascading menus.
 * pop-up menus are distinguished from a standard menu in that it is not attached to a menu bar in a fixed location. (Also known as contextual menu).
 * -the toolbar is a collection of buttons grouped according to function.
 * -the buttons are represented as icons to give a clue as to their function.
 * -toolbars are also configurable.

__**6.5 Form fill**__


 * from fill interfaces are used to gather information such as name and address.
 * individual boxes are called fields and are frequently marked with an asterisk to indicate that an entry is mandatory


 * Wizards
 * wizard is the name given to a style of interaction which leads the user by the metaphorical hand step-by-step through a series of questions that answers, pick-lists and other kinds of widgets to achieve a task.
 * wizards are used to install hardware and applications.
 * wizards represent a complex task in ‘bite-sized’ pieces.

__**6.6 Input devices**__


 * touch screens
 * touch screens appear visually identical to a normal monitor but, the screens are sensitive to the touch of the finger.
 * they function through either infra-red sensitivity or electrical capacitance.
 * light pens


 * light pens were arguably the original pointing device.


 * the mouse
 * the mouse has become the default pointing device.
 * a mouse might be cordless, using infra-red to communicate with the host computer.
 * handwriting recognition


 * problems with handwriting recognition include:


 * 1) quite slow
 * 2) inaccurate
 * 3) requires the user to ‘train’ the device to recognize your handwriting
 * 4) many people can type faster than writing by hand


 * __6.7 Output devices__**


 * display devices
 * monitor most fundamental output device.
 * output device is driven by hardware – a graphics card which with windows-based systems is likely to be a third party specialist deice and which will vary with respect to the screen resolutions and palette of colours it can support.
 * data projectors
 * less resolution but usually results in a huge image projection.
 * speech
 * speech synthesis works well enough (a) to understand what the computer is saying to us and (b) to do a pretty good job at pronouncing all but the most obscure of words. But like sound we generally do not use it.
 * speech synthesis cannot imitate the full spectrum of human cadences and intonations, but speech synthesis systems can read text files and output them in a very intelligible, if somewhat dull, voice.
 * screen reader produces synthesized voice output for text displayed on the computer screen, as well as for keystrokes entered on the keyboard.
 * printers and plotters
 * a printer is a device that prints text or illustrations on paper, while a plotter draws pictures.
 * plotters differ from printers in that they draw lines using a pen.
 * haptics
 * haptics refer to the sense of touch. However, haptics allow us to be in touch with interactive devices and media in a way which is direct and immediate.
 * most widespread haptic device is those game controllers which incorporate so-called force-feedback.
 * an example of haptics is the ‘silent alert’ vibration of a mobile phone.


 * __6.8 virtual reality (VR)__**


 * virtual reality can be divided up into 2 basic forms:
 * Immersive and non-immersive.
 * Immersive virtual reality requires the users to wear a light-excluding helmet which houses the display, and a data glove which facilitates the manipulation of virtual objects within virtual reality.
 * Non-immersive virtual reality, in contrast, is displayed on a computer’s monitor.
 * while immersive virtual reality has captured the public imagination, desktop virtual reality is more commonly found.


 * __6.9 VR input and output devices__**


 * data glove
 * gloves equipped with sensors (data gloves) are able to sense the movements of the hand which are translated into corresponding movements in the virtual environment.
 * Head-mounted display (HMD)
 * An HMD is a light proof and rather heavy helmet isolating the wearer from the world and consists of two colour displays located in line with one’s eyes and a pair of stereo earphones. An HDM also has a head tracker which provides information about the user’s position and orientation in space.