HCI USER INTERFACE & USER SUPPORT
We shall study computer factors in HCI and User support in HCI; the input and output
devices approaches to user support, types of user support and the requirements for user
support.
A user interface is the system by which people user interact with a machine. The user
interface includes hardware (physical) and software (logical) components. User interfaces
exist for various systems and provide a means of:
a) Input, allowing the users to manipulate a system
b) Output, allowing the system to indicate the effects of the users' manipulation
The user interface is a component of a computer or its software which can be visualized,
heard, touched, interacted with, run and understood by the common people or users of the
computer. A computer system is made up of various elements each of these elements
affects the interaction
a) input devices – text entry and pointing
b) output devices – screen (small & large), digital paper
c) virtual reality – special interaction and display devices
d) physical interaction – e.g. sound, haptic, bio-sensing
e) paper – as output (print) and input (scan)
f) memory – RAM & permanent media, capacity & access
g) processing – speed of processing, networks
The devices dictate the styles of interaction that the system supports. If we use different
devices, then the interface will support a different style of interaction.
Input Devices
An input device is
” “a device that, together with appropriate software, transforms information from the user
into data that a computer application can process”
Input is concerned with recording and entering data into computer system and issuing
instruction to the computer. In order to interact with computer systems effectively, users
must be able to communicate their interaction in such a way that the machine can interpret
them.
Therefore, input devices can be defined as: a device that, together with appropriate
software, transforms information from the user into data that a computer application can
process.
The choice of input device should contribute as positively as possible to the usability of the
system. In general, the most appropriate input device will be the one that:
Matches the physiology and psychological characteristics of users, their training and
their expertise. For example, older adults may be hampered by conditions such as
arthritis and may be unable to type; inexperienced users may be unfamiliar with
keyboard layout.
, Is appropriate for the tasks that are to be performed. For example, a drawing task
from a list requires an input device that allows continuous movement; selecting an
option from a list requires an input device that permits discrete movement.
Is suitable for the intended work and environment. For example, speech input is
useful where there is no surface on which to put a keyboard but is unsuitable in
noisy condition; automatic scanning is suitable if there is a large amount of data to
be generated.
Input devices include
a) Text entry devices
b) Handwriting Recognition
c) Speech Recognition
d) Positioning, Pointing and Drawing
e) Cursor Keys
Text entry devices
There are many text entry devices as given below:
Keyboard
The most common method of entering information into the computer is through a
keyboard.
When considering the design of keyboards, both individual keys and grouping
arrangements need to be considered. The physical design of keys is obviously important.
Alterations in the arrangement of the keys can affect a user’s speed and accuracy. Various
studies have shown that typing involves a great deal of analyses of trained typists suggest
that typing is not a sequential act, with each key being sought out and pressed as the letters
occur in the works to be typed. Rather, the typist looks ahead, processes text in chunks, and
then types it in chunks
.
QWERTY Keyboard
Most people are quite familiar with the layout of the standard alphanumeric keyboard,
often called the qwerty keyboard, the name being derived from the first letters in the upper
most row from left to center. This design first became a commercial success when used for
typewriters in the USA in 1874, after many different prototypes had been tested.
The arrangement of keys was chosen in order to reduce the incidence of keys jamming in
the manual typewriters of the time rather than because of any optimal arrangement for
typing.
For example, the letters ‘s’, ,t, and ‘h’ are far apart even though they are far apart even
though they are frequently used together.
Alphabetic keyboard
One of the most obvious layouts to be produced is the alphabetic keyboard, in which the
letters are arranged alphabetically across the keyboard. It might be expected that such a
layout would make it quicker for untrained typists to use, but this is not the case. Studies
We shall study computer factors in HCI and User support in HCI; the input and output
devices approaches to user support, types of user support and the requirements for user
support.
A user interface is the system by which people user interact with a machine. The user
interface includes hardware (physical) and software (logical) components. User interfaces
exist for various systems and provide a means of:
a) Input, allowing the users to manipulate a system
b) Output, allowing the system to indicate the effects of the users' manipulation
The user interface is a component of a computer or its software which can be visualized,
heard, touched, interacted with, run and understood by the common people or users of the
computer. A computer system is made up of various elements each of these elements
affects the interaction
a) input devices – text entry and pointing
b) output devices – screen (small & large), digital paper
c) virtual reality – special interaction and display devices
d) physical interaction – e.g. sound, haptic, bio-sensing
e) paper – as output (print) and input (scan)
f) memory – RAM & permanent media, capacity & access
g) processing – speed of processing, networks
The devices dictate the styles of interaction that the system supports. If we use different
devices, then the interface will support a different style of interaction.
Input Devices
An input device is
” “a device that, together with appropriate software, transforms information from the user
into data that a computer application can process”
Input is concerned with recording and entering data into computer system and issuing
instruction to the computer. In order to interact with computer systems effectively, users
must be able to communicate their interaction in such a way that the machine can interpret
them.
Therefore, input devices can be defined as: a device that, together with appropriate
software, transforms information from the user into data that a computer application can
process.
The choice of input device should contribute as positively as possible to the usability of the
system. In general, the most appropriate input device will be the one that:
Matches the physiology and psychological characteristics of users, their training and
their expertise. For example, older adults may be hampered by conditions such as
arthritis and may be unable to type; inexperienced users may be unfamiliar with
keyboard layout.
, Is appropriate for the tasks that are to be performed. For example, a drawing task
from a list requires an input device that allows continuous movement; selecting an
option from a list requires an input device that permits discrete movement.
Is suitable for the intended work and environment. For example, speech input is
useful where there is no surface on which to put a keyboard but is unsuitable in
noisy condition; automatic scanning is suitable if there is a large amount of data to
be generated.
Input devices include
a) Text entry devices
b) Handwriting Recognition
c) Speech Recognition
d) Positioning, Pointing and Drawing
e) Cursor Keys
Text entry devices
There are many text entry devices as given below:
Keyboard
The most common method of entering information into the computer is through a
keyboard.
When considering the design of keyboards, both individual keys and grouping
arrangements need to be considered. The physical design of keys is obviously important.
Alterations in the arrangement of the keys can affect a user’s speed and accuracy. Various
studies have shown that typing involves a great deal of analyses of trained typists suggest
that typing is not a sequential act, with each key being sought out and pressed as the letters
occur in the works to be typed. Rather, the typist looks ahead, processes text in chunks, and
then types it in chunks
.
QWERTY Keyboard
Most people are quite familiar with the layout of the standard alphanumeric keyboard,
often called the qwerty keyboard, the name being derived from the first letters in the upper
most row from left to center. This design first became a commercial success when used for
typewriters in the USA in 1874, after many different prototypes had been tested.
The arrangement of keys was chosen in order to reduce the incidence of keys jamming in
the manual typewriters of the time rather than because of any optimal arrangement for
typing.
For example, the letters ‘s’, ,t, and ‘h’ are far apart even though they are far apart even
though they are frequently used together.
Alphabetic keyboard
One of the most obvious layouts to be produced is the alphabetic keyboard, in which the
letters are arranged alphabetically across the keyboard. It might be expected that such a
layout would make it quicker for untrained typists to use, but this is not the case. Studies
