UNIT 1 LESSON 1 PART 1 AND 2

Part 1 and 2 of HCI

Human Computer Interface

Human Computer Interface

is a multidisciplinary field of study focusing on the design of computer technology and the interaction between humans (the users) and computers. HCI become popular and cover almost all forms of information technology design.

Humans interact with computers in many ways, the interface between humans and computers is essential to facilitate this interaction. Desktop applications, internet browsers, handheld computers, ERP, and computer kiosks make use of the widespread graphical user interfaces (GUI) of today.

Generally, the goal of human-computer interaction is to produce a user interface that makes it easy, effective, efficient, and enjoyable (user-friendly) to use.

1970

The rise of the Personal Computer

1980

Graphical User Interface (GUI)

1990

The Internet and Collaborative

2000

Mobile Computing and Beyond.

Ubiquitous Communication

Computers will communicate through high-speed local networks, nationally over wide-area networks, and portably via infrared, ultrasonic, cellular, and other technologies. Data and computational services will be portably accessible from many if not most locations to which a user travels.

High Functionality Systems

Systems have large numbers of functions associated with them. There will be so many systems that most users, technical or non-technical, will not have time to learn them traditionally (e.g., through thick manuals).

Mass Availability of Computer Graphics

Computer graphics capabilities such as image processing, graphics transformations, rendering, and interactive animation will become widespread as inexpensive chips become available for inclusion in general workstations.

Mixed Media

Systems will handle images, voice, sounds, video, text, and formatted data. These will be exchangeable over communication links among users. The separate worlds of consumer electronics (e.g., stereo sets, VCRs, televisions) and computers will partially merge. Computer and print worlds will continue to cross assimilate each other.

High-bandwidth Interaction

The rate at which humans and machines interact will increase substantially due to the changes in speed, computer graphics, new media, and new input/output devices. This will lead to some qualitatively different interfaces, such as virtual reality or computational video.

Large and Thin Displays

New display technologies will finally mature enabling very large displays and also displays that are thin, lightweight, and have low power consumption. This will have large effects on portability and will enable the development of paper-like, pen-based computer interaction systems very different in feel from desktop workstations of the present.

Embedded Computation

will pass beyond desktop computers into every object for which uses can be found. The environment will be alive with little computations from computerized cooking appliances to lighting and plumbing fixtures to window blinds to automobile braking systems to greeting cards. To some extent, this development is already taking place.

Group Interfaces

Interfaces to allow groups of people to coordinate will be common (e.g., for meetings, for engineering projects, for authoring joint documents). These will have major impacts on the nature of organizations and the division of labor. Models of the group design process will be embedded in systems and will cause increased rationalization of design.

User Tailorability

Ordinary users will routinely tailor applications to their use and will use this power to invent new applications based on their understanding of their domains. Users, with their deeper knowledge of their knowledge domains, will increasingly be important sources of new applications at the expense of generic systems programmers (with systems expertise but low domain expertise).

Information Utilities

Public information utilities (such as CompuServe, home banking and shopping, etc.) and specialized industry services (e.g., weather for pilots) will continue to proliferate. The rate of proliferation will accelerate with the introduction of high-bandwidth interaction and the improvement in the quality of interfaces.

Human Computer Interface

Consists of three parts:

Human- could be an individual user or a group of users.

Computer- could be any technology ranging from the general desktop computer to a large scale computer system.

Interaction-any direct or indirect communication between a human and computer.

Human

 Humans are limited in their capacity to process information. This has important implications for design.

 Information is received and responses are given via several input and output channels:

 visual channel

 auditory channel

 haptic channel

 movement

 Information is stored in memory:

 sensory memory

 short-term (working) memory

 long-term memory

 Information is processed and applied:

 reasoning

 problem-solving

 skill acquisition

 error

 Emotion influences human capabilities.

 Users share common capabilities but are individuals with differences, which should not be ignored.

Computer

 Input devices for interactive use, allowing text entry, drawing, and selection from the screen:

 text entry: traditional keyboard, phone text entry, speech and handwriting

 pointing: principally the mouse, but also touchpad, stylus, and others

 3D interaction devices

 Output display devices for interactive use:

 different types of screen mostly using some form of a bitmap display

 large displays and situated displays for shared and public use

 the digital paper may be usable shortly

 Virtual reality systems and 3D visualization have special interaction and display devices.

 Various devices in the physical world:

 physical controls and dedicated displays

 sound, smell, and haptic feedback

 sensors for nearly everything including movement, temperature, bio-signs

 Paper output and input: the paperless office and the less-paper office:

 different types of printers and their characteristics, character

styles, and fonts

 scanners and optical character recognition

 Memory:

 short-term memory: RAM

 long-term memory: magnetic and optical disks

 capacity limitations related to document and video storage

 access methods as they limit or help the user

 Processing:

 the effects when systems run too slow or too fast, the myth of the infinitely fast machine.

 limitations on processing speed.

 networks and their impact on system performance.

Interaction

The interaction between the user and the system has four parts:

 User

 Input

 System

 Output

Popular Metaphors for Computers

 computer as a vast library (Memex, 1945)

 computer as a giant calculator (ENIAC, 40s-50s)

 computer as an intelligent assistant (Licklider, 1957)

 computer as sketchpad (Sutherland, 1962)

 computer as tool or typewriter (Engelbart, 1963)

 computer as a human pretender (Weizenbaum, ‘60s)

 computer as a network (Taylor, 1968)

 computer as a book (portable) (Kay, Xerox PARC)

 computer as desktop/windows (Xerox PARC, ‘70s)

 computers for the rest of us (Apple, 1984)

Successful Metaphors

 text editing as using a typewriter

 voice mail as answering machine or mailbox

 data as files (in folders or directories)

 deleting a file as throwing it in the trash

 applications as tools (sometimes with icons)

 programming as building objects

 programming as directing actors on a stage

 applications as agents

Interaction Styles

Interaction can be seen as a dialog between the

computer and the user. The choice of interface style

can have a profound effect on the nature of this

dialog. The most common interface styles and the

different effects these have on the interaction. There

are several common interface styles including.

Command Line Interface

It provides a means of expressing instructions to be computer directly, using function keys, single characters, abbreviations, or whole word commands.

Menus

is a list of options or commands presented to the user of a computer or communications system. A menu may either be a system's entire user interface, or only part of a more complex one.

Natural Language

Question/Answer and Query Dialog The user is asked a series of questions (mainly with yes/no responses, multiple -choice, or codes) and so is led through the interaction step by step.

Form-Fills and Spreadsheets

Form-filling interfaces are used primarily for data entry but can also be useful in data retrieval applications. The user is presented with a display resembling a paper form, with slots to fill in.

WIMP Interface

stands for Windows, Icons, Menus, and Pointers (or maybe Windows, Icons, Mouse, Pull-down menus). It is also the style of graphical user interface that uses the above-mentioned common widgets.

Point and Click Interfaces

________________ are the actions of a computer user moving a pointer to a certain location on a screen (pointing) and then pressing a button on a mouse, usually the left button (click), or another pointing device.

Three Dimensional Interfaces

Virtual reality is one of the best examples of three dimensional interfaces, but VR is only a part of a range of 3D techniques available to the interface designer.