1.1 Basic Concepts of Input-Process-Output Cycle

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1.1 Basic Concepts of Input-Process-Output
Cycle

• A computer is a very powerful electronic machine
• A computer can
• store a huge amount of data
• perform complicated calculations
• produce the calculated results on different media

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1.1 Basic Concepts of Input-Process-Output
Cycle

• The process of a computer task can be divided
  into three stages
• Input
• Process
• Output

Input-Process-Output cycle
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1.1 Basic Concepts of Input-Process-Output
Cycle

• In our daily lives, many activities involve the
  Input-Process-Output cycle.

Input-Process-Output cycle
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1.1 Basic Concepts of Input-Process-Output
Cycle

• For a computer, the Input-Process-Output cycle
  usually involves operations and hardware.

Input Enter data and commands into a computer
via one or more input devices.
Process The CPU works on the data according to
the commands provided in the input stage.
Output The computer shows the processed
result on the output devices specified in the
input stage.
The Input-Process-Output cycle in a computer
process
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1.1 Basic Concepts of Input-Process-Output
Cycle

• For a computer, the Input-Process-Output cycle
  usually involves operations and hardware.

Input Enter data and commands into a computer
via one or more input devices.
Process The CPU works on the data according to
the commands provided in the input stage.
Output The computer shows the processed
result on the output devices specified in the
input stage.
The Input-Process-Output cycle in a computer
process
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1.2 Use of Stored Programs

• Programs
• Computers themselves will not function if no
  command is given.
• A program
• A sequence of commands
• Should be provided to the computer in order to
  instruct the computer to complete a specific task
• Will be fetched by the computer and the commands
  will be executed one by one

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1.2 Use of Stored Programs

• Stored programs
• Enable computers to do tasks automatically,
  repeatedly and accurately
• Saved in the read-only memory (ROM) of many home
  appliances and machines
• Executed by the microprocessor to control the
  operations of the machines.

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1.2 Use of Stored Programs

• Stored programs

A modern microwave oven has stored programs to
decide the appropriate temperature and cooking
time for the food.
A modern video recorder records TV programmes
automatically according to the recording schedule
preset by users.
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1.2 Use of Stored Programs

• Stored programs
• Found in traditional mechanical products
• Mechanical music boxes
• Old-fashioned sewing machines

A mechanical music box and traditional sewing
machine are examples of mechanical machines with
stored programs.
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1.2 Use of Stored Programs

• Stored programs
• Found in traditional mechanical products
• Mechanical music boxes
• Old-fashioned sewing machines

A mechanical music box and traditional sewing
machine are examples of mechanical machines with
stored programs.
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1.3 Difference between Data and Information

• Data
• A collection of raw facts that are not organized
• Has no meaning on their own
• Information
• Data that has been organized
• Meaningful and useful for decision making

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1.3 Difference between Data and Information
Data is processed into information.
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1.3 Difference between Data and Information
Data is processed into information.
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1.4 Types of Data

• Data can be converted into digital forms with the
  help of appropriate input devices
• Different types of data

Text
Audio
Images
Videos
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1.4 Types of Data
Video
Text
Image
Audio
Different types of data
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1.4 Types of Data

• Text
• Examples
• Characters
• Numbers
• Symbols
• Can be represented by certain character coding
  systems
• American Standard Code for Information
  Interchange (ASCII)
• Unicode
• Big5 code

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1.4 Types of Data

• Text
• Input devices for text entry
• Keyboard
• Handwriting board
• Scanner with optical character recognition (OCR)
  software
• Voice recognition system

A handwriting board
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1.4 Types of Data

• Text
• When we enter text data with an input device, the
  text data is transformed into binary codes.
• The binary codes can be further processed or
  stored in a computer.

Chinese Character Big5 code Unicode
? 1010 0100 1110 0000 0110 0101 1110 0101
? 1011 1110 1100 0000 0101 1011 0111 1000
? 1010 0100 1101 0000 0101 1001 0010 1001
Different character coding systems may have
different codes for the same character.
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1.4 Types of Data

• Image
• Examples
• Photographs
• Drawings
• Handwritten text
• Can be inputted into a computer by a scanner.
• Can be converted into a rectangular grid of
  colour dots (known as pixels).
• Each colour dot is represented by a string of
  binary codes in a computer.
• The digital representation of a collection of
  colour dots of an image is known as a bitmap
  image.

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1.4 Types of Data

• Image

Common methods of producing a digital image
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1.4 Types of Data

• Image
• Common devices that produce bitmap images
• Digital camera
• Mobile phone (with built-in camera)
• Scanner

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1.4 Types of Data

• Audio
• Use of audio files in a computer
• Record music
• Speeches
• Any kind of audio signals in digital form
• Audio signals can be captured into a computer by
  means of a microphone.
• The analogue audio signals are converted to a
  stream of digital audio signals by a sound card.
• The computer is able to edit and store it or
  reproduce the audio with speakers.
• Popular file formats for digital audio files
• WAV
• AAC
• MP3

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1.4 Types of Data

• Audio

Analogue audio can be digitized for editing,
playback and storage
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1.4 Types of Data

• Video
• A sequence of images representing a scene in
  motion
• A digital video file consists of a stream of
  digital data that contains both video and audio.
• A web cam can capture video and audio (with its
  internal microphone) into a digital video file.
• A video capture card can convert analogue video
  signals from external sources into digital video
  files.
• Both digital video cameras and digital cameras
  can capture and record video in a digital form
  and store them as digital computer files.
• Digital computer files can be transferred across
  computers without the need of any further
  conversion.

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1.4 Types of Data

• Video

Analogue videos can be digitized for editing,
playback and storage
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1.4 Types of Data

• Video

Analogue videos can be digitized for editing,
playback and storage
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1.5 Components of an Information System

• Information System
• Basically a system that accepts data as input and
  transforms it into information as output via the
  Input-Process-Output cycle
• The transformation can be either a manual or an
  automated process.
• In general, it consists of five interrelated
  components

Processes
Purposes
Personnel
Technologies
Data
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1.5 Components of an Information System

• Purposes
• Some of the most common reasons for implementing
  an information system
• Automate an existing manual process
• Improve an existing system
• Fix system problems
• The current situation of a school library
• Operate in manual mode
• Students need to come to the library and search
  for books on the bookshelves.
• If a student wants to borrow a book, the
  librarian will write down a record of it in a
  logbook.
• Teachers sometimes need to check the logbook to
  see which subjects are most popular.

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1.5 Components of an Information System

• Purposes
• The purposes of a library system
• Help students search for the books efficiently
• Help librarians track the status of a book
  efficiently
• Help teachers figure out which subjects are most
  popular
• Help in stocktaking at the end of each semester
• Automatically generate reports of overdue books

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1.5 Components of an Information System

• Purposes

The library system of the Chinese University of
Hong Kong
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1.5 Components of an Information System

• Data
• The major component of an information system
• Examples
• In a payroll information system, data can be
  employees names, salaries or grades.
• In a multimedia information system, data can be
  digital images or digital videos.
• After the information system has collected the
  data, the data will be stored in a main database.
  
• A main database is a structured collection of
  records or data that are stored in a computer
  system so that they can be retrieved by query
  languages.

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1.5 Components of an Information System

• Processes
• Work with data to achieve the purposes or
  objectives
• Some examples of processes
• Generating bank statements
• Categorizing data
• Printing management reports
• All processes are combined together to form an
  information system.

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1.5 Components of an Information System

• Processes
• Processes of the food ordering information system
  in a restaurant
• Receiving and transferring customer food orders
• Transforming order to kitchen format
• Generating customer receipt
• Aggregating goods sold and inventory data
• Producing management reports

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1.5 Components of an Information System

• Technologies
• An information system is a computer-based system
  that relies on technologies including

Hardware
Software
Network
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1.5 Components of an Information System

• Technologies
• Hardware
• Refers to all the physical components
• In a point-of-sale system, computer hardware
  includes
• Monitors
• Keyboards
• Bar code scanners
• Printers
• Also covers any media used by machines, for
  example
• ATM cards
• Credit cards
• Octopus cards

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1.5 Components of an Information System

• Technologies
• Hardware

Point-of-sale terminal in a supermarket
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1.5 Components of an Information System

• Technologies
• Software
• A sequence of instructions which instructs the
  information system to perform specific tasks
• Two kinds of software that would be used in an
  information system

System software
Application software
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1.5 Components of an Information System

• Technologies
• Software
• System software
• Manages computer resources such as hard disks,
  CPUs, files, the main memory and all devices that
  are used to control the computer
• An operating system
• A part of system software
• Examples Microsoft Windows, UNIX
• Application software
• Designed for users to perform specific tasks
• Database software
• A type of application software
• Example Microsoft Access
• Stores records or data in a computer system and
  organizes them in a structured way by using tables

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1.5 Components of an Information System

• Technologies
• Network
• Some information systems may not only be used in
  a single computer.
• They may be used in a group of computers
  interconnected via the Internet or the intranet.
• An online cinema information system using network
  technologies
• A server is set up at the head office.
• This server is connected to a database server.
• Customers can use a web browser to submit a
  ticket-ordering request to the server

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1.5 Components of an Information System

• Personnel
• A major component of all information systems
• They use, develop or manage an information system
• Two types of roles
• End users
• Information system (IS) specialists

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1.5 Components of an Information System

• Personnel
• End users
• Use an information system or an information
  product
• Information system (IS) specialists
• Develop or manage information systems
• Usually from the information system department
  which deliver IT services to an organization
• Examples
• Systems analysts
• Programmers
• Technicians
• Network managers
• Data entry operators

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1.5 Components of an Information System

• Personnel
• Information system (IS) specialists
• Systems analyst
• Responsible for the research, planning and
  implementation of the information system
  according to the requirements defined by end
  users
• Analyze the cost, study the feasibility, design
  the system using any new technologies and
  estimate the time frame of the implementation
• Programmer
• Responsible for converting the system design
  developed by the systems analysts into program
  codes

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1.5 Components of an Information System

• Personnel
• Information system (IS) specialists
• Technician
• Responsible for managing the information system
  such as performing the backup of the system and
  monitoring its resource usages
• Network Manager
• Responsible for monitoring the availability and
  performance of the communication between computer
  systems
• Data Entry Operator
• Responsible for entering data into the
  information system before end users can use it

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1.5 Components of an Information System

• Personnel
• Information system (IS) specialists
• Technician
• Responsible for managing the information system
  such as performing the backup of the system and
  monitoring its resource usages
• Network Manager
• Responsible for monitoring the availability and
  performance of the communication between computer
  systems
• Data Entry Operator
• Responsible for entering data into the
  information system before end users can use it

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1.6 Information Processes

• The information life cycle
• The processes of transforming data into useful
  information
• Normally there are seven information processes

Data collection
Presentation
Organization
Transmission
Storage
Analysis
Processing
An information life cycle
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1.6 Information Processes

• Data Collection
• The activity of collecting raw data from the
  outside world so that it can be put into an
  information system
• Methods
• Personal interviews
• Telephone interviews
• Questionnaires
• Experiments
• The Internet
• These methods can be used separately or combined
  together.

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1.6 Information Processes

• Data Collection

Collecting data through a personal interview
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1.6 Information Processes

• Organization
• Collected data must be organized into certain
  formats so that it can be further processed.
• The data can be represented in
• Text
• Images
• Audio
• Videos
• Ways to organize data
• Putting data into paper-based forms or electronic
  forms by its category
• Inserting data into related database tables or
  spreadsheets
• Grouping images to create an animation

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1.6 Information Processes

• Organization

• Manual validity check
• Check for completeness.
• Check whether the contextual information is
  included.
• Check whether the answers are reasonable and
  legible.

• Data categorization
• Divide the raw data into different groups.
• Sort the raw data into a specific order for
  facilitating subsequent data entry procedure.

• Data-logging
• Keep track of incoming data.

Stages of data preparation
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1.6 Information Processes

• Storage
• Organized data must be stored in storage media so
  that they can be retrieved for processing later.
• Two kinds of storage media
• Non-digital media
• Paper
• Files
• Digital media
• CD-ROMs
• DVDs
• Hard disks
• Floppy disks
• Magnetic tapes

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1.6 Information Processes

• Storage
• Most of the information systems use database
  software to store data.
• Database software uses direct access devices such
  as hard disks as storage media.

Financial data of a company can be backed up in
magnetic tapes.
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1.6 Information Processes

• Processing
• Different kinds of processing
• Data processing
• Sorting
• Searching
• Merging
• Calculating
• Word processing
• Image processing
• Video processing
• Audio processing

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1.6 Information Processes

• Processing
• An example of information processing in a human
  resource management system
• Photos given by employees may be in a different
  format or size other than the system requires.
• The photos may need to be processed by image
  editing software.
• Sorting (data processing) on employee names may
  be necessary to speed up data search.

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1.6 Information Processes

• Processing

A photo can be processed by using image editing
software Paint.NET.
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1.6 Information Processes

• Analysis
• Analysis is performed on the processed data to
  extract useful information.
• An analysis method using spreadsheets to create
  models to produce statistics or trend analysis
• Analyzed information can be presented in graphs
  or charts.
• For the food ordering system of a restaurant
• The database is analyzed to find most popular
  foods.
• The staff is then informed to purchase more of
  these foods.

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1.6 Information Processes

• Transmission
• The process of sending information from one
  computer system to another
• A common protocol must be used to communicate
  between different systems.
• The Internet
• It uses TCP/IP for data communication.
• Data in different systems may be in different
  formats.
• Extensible Markup Language (XML) provides a
  common data format for different information
  systems.

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1.6 Information Processes

• Transmission

Transmitting purchasing orders on an online
supermarket web site
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1.6 Information Processes

• Presentation
• Information can be presented through different
  media
• Audio
• Video
• Screen displays
• Printed outputs

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1.6 Information Processes

• Presentation
• Various ways of presenting information

Tables
Charts
Lists
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1.6 Information Processes

• Presentation
• Various ways of presenting information

Tables
Charts
Lists
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1.7 Information Technology and the Information
Age

• The rapid development of information and
  communication technology presents us with a large
  amount of information every day.
• It not only makes the Internet an information
  enriched network but also a platform providing
  numerous web-based services.
• Our society has now moved into the Information
  Age.

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1.7 Information Technology and the Information
Age

• What is the Information Age?
• Refers to a period beginning in the last quarter
  of the 20th century
• With the advancement of distribution of
  information by telecommunication networks and
  especially the Internet, information spreads
  widely and rapidly.
• People can access all kinds of up-to-date
  information easily anywhere and anytime at a very
  low cost.

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1.7 Information Technology and the Information
Age

• What is the Information Age?

All kinds of up-to-date information can now be
easily obtained.
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1.7 Information Technology and the Information
Age

• Living in a Knowledge-based Society
• A society employs knowledge, information
  technology and communication systems to all
  citizens
• Knowledge is the major asset in a knowledge-based
  society.
• Factors to determine the success of a
  knowledge-based society

Communication Networks
People
Computers
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1.7 Information Technology and the Information
Age

• Living in a Knowledge-based Society
• Computers
• Essential equipment for producing, manipulating,
  storing and distributing knowledge
• Must be prevalent in the society
• Communication Networks
• Should be of high transmission speed and wide
  coverage at low cost
• Examples
• Telecommunication networks
• Broadband services
• The Internet
• Media broadcasting networks

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1.7 Information Technology and the Information
Age

• Living in a Knowledge-based Society
• People
• Must be information literate in order to handle
  the vast amounts of information encountered every
  day
• An information literate should be able to
• determine the nature and extent of the
  information needed
• access information effectively and efficiently
• question the information source
• use information effectively to accomplish a
  specific task
• convert information from one form to another
  desirable form using information technologies
• create new knowledge from collected information
  through analytical processes with IT software
• use information ethically and legally

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1.7 Information Technology and the Information
Age

• Living in a Knowledge-based Society
• People
• The knowledge and skills required for effective
  use of IT changes from time to time.
• Lifelong learning has become imperative.

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1.7 Information Technology and the Information
Age

• Living in a Knowledge-based Society
• People
• The knowledge and skills required for effective
  use of IT changes from time to time.
• Lifelong learning has become imperative.