Title: Introduction to Information Technology
1Introduction to Information Technology
2Definition for IT
- Information Technology (IT) is a broad subject
concerned with the use of technology in managing
and processing information, especially in large
organizations - IT deals with the use of electronic computers and
computer software to convert, store, protect,
process, transmit, and retrieve information - Information Technology is also known as
Information Communication Technology (ICT)
3Why is it Important ?
- Rapid deployment and set-up
- Access to critical real time decision support
information - Delivery of high value and high quality
information matched against pre-defined - Ease of use and flexibility for operating in a
high stress, limited resource environment. - Systems that run in a connected and stand-alone
mode - Systems that facilitate information sharing and
communication locally and internationally - Open systems, flexible, scalable, and secure
application and technology solutions. - Comprehensive and flexible report generation
- Adapting systems to meet regulatory, cultural,
social, skill and usage requirements.
4What is a Computer?
- A Computer is a programmable, multipurpose
machine that accepts data (e.g. raw data, facts
figures) and processes, or manipulates it into
information we can use, such as summaries or
totals
E.g. An automatic teller machine (ATM) computes
the deposits and withdrawals to give you the
total in your account.
5Why Computers are Needed?
- Fundamental Characteristics, to Increase
- Accuracy
- To process data with high precision
- Speed
- To manipulate data with high speed compared to
manual processes - Storage capacity
- To increase storing capability
6Why Computers are Needed?
- The three fundamental characteristics enable the
following by - Increased Productivity
- Efficient Decision Making
- Cost Reduction
7Why Computers are Needed?
- Hand over our recursive tedious work to the
computer
- Typewriter Word Processor/Printer
- Card file Database Management System
8Why Computers are Needed?
- letter e-mail
- phone dialler Communication Management program
9Functions of a Computer
- Input Operations
- Arithmetic Operations
- Logic Operations
- Output Operations
- Storage Operations
10Functions of a Computer Contd.
- Input Operations
- computer can accepts data instructions.
- Arithmetic Operations
- Computer can process arithmetic operations such
as Addition, Multiplication, Subtraction
Division - Logic Operations
- Computer can perform logic operation such as
- AND, OR, NOT .
11Functions of a Computer Contd.
- Output Operations
- Computer can produce an output as a screen view,
as a hard copy, as a sound output. - Storage Operations
- Computer can store a large amount of data
programs permanently perform tasks later.
12Components of a Computer System
13Components of a Computer System Input Units
- Input units are used to feed data and
instructions to the computer system. - Input units provide the interface between the
outside world and the computer system.
14Components of a Computer System Input Units
- The most common examples for the input units are
- Keyboard
- Mouse
- Other pointing devices.
15Components of a Computer System Output Units
- The output units of a computer systems, are used
to produce the results of the operations
performed by the computer. - Displays various other messages to the user.
16Components of a Computer System Output Units
- The most common examples for the output units are
- Display monitors
- Printers
17Components of a Computer System Internal Storage
- This is also called as the main memory, and most
commonly RAM (Random Access Memory). - Volatility is one of the specific features of the
main storage. That is, it requires continuous
supply of electrical power to retain information.
18Components of a Computer System Internal Storage
- The internal store is used to
- Receive the commands and data from the input
units. - Store the information ready to be sent to the
output units. - Store the currently running program(s).
- Store the data required for the currently running
program(s). - Store the intermediate data generated by the
currently running program(s).
19Components of a Computer System External Storage
- The external storage units are non-volatile.
- They are used to store programs and data for
future use. - They are also used when the capacity of the
internal storage is insufficient to keep the
currently running program(s) and the data
required.
20Components of a Computer System Arithmetic
Logic Unit
- Both the Arithmetic Logic Unit (ALU) and the
Control Unit of a computer system are
collectively called as the Central Processing
Unit (CPU) of a computer system. - When all the electronics required to implement
the functions of the CPU are included in a single
Integrated Circuit(IC) chip, it is called a
Microprocessor.
21Components of a Computer System Arithmetic
Logic Unit
- The ALU performs all the arithmetic and logical
operations required during the execution of the
programs.
22Components of a Computer System Control Unit
- Main function of the control unit is to issue the
control signals to all the components to activate
the role of each of them during the process of
running a program.
23Components of a Computer System Control Unit
- It receives the individual instructions in a
program one by one and then decodes them to
identify the type and the sequence of the control
signals to be generated. - The control unit is responsible for the overall
control of the system.
24Hardware, Software and Firmware
- Hardware
- Consists of all machinery and equipments which
comprise a computer system . - All tangible items in a Computer system fall into
the category of hardware. - That is, in a Computer system the hardware
includes, among other devices, the Keyboard, the
Screen, the Printer and the Computer or
processing devices itself.
25Hardware, Software and Firmware...
- Software
- Intangible in nature.
- Consists of the step-by-step instructions that
tell the computer what to do. - Needs some media to exist.
- Runs on top of hardware making the hardware
usable. - Software is divided into two basic categories
- Application Software
- System Software
26Hardware, Software and Firmware...
- Firmware
- Inbuilt software which has been installed by the
manufacture. - The permanent pieces of software which are not
supposed to be altered by the users are presented
in this form. - Firmware brings some flexibilities in the
manufacturing process of the computer systems. - E.g. Machine-language programs stored
- on ROM chip
27System Software
- System Software provides the interface between
the hardware and the application software. - In this context it hides the hardware
complexities and also brings the different
hardware configurations into common platforms.
28System Software
- Enables the Application software to interact with
the computer help it manage its internal
resources. - System software make the hardware of the computer
system accessible by the application programs and
the users.
29System Software
The systems software consists of several
programs, one of the most important of which is
the operating system. The operating system acts
as the master control program that runs the
computer.
30Application Software
- Application software may be either customized or
Packaged - Customized Software
- is the Software designed for a particular
customer according to their needs. - Packaged Software
- Also called as Software Package, is the kind of
Off-the-Shelf program developed for the general
use.
31Packaged Software
Word Processing The Most popular kind of
applications program, allows a person to use a
computer to create, edit, save and print
documents. Used to prepare letters, memos,
reports, manuscripts, etc. E.g. Microsoft Word
32Packaged Software
Spreadsheet Allows a person to use rows, columns
and formulas to display, analyse and summarise
data, mostly numerical data. Used to do budgets,
sales projections, financial plans, etc. E.g.
Microsoft Excel, Lotus 1-2-3
33Packaged Software
Database Manager Allows a person to use a
computer to define files, records within files
and data elements within records in a relatively
easy manner and provide a convenient method to
access, update and create reports from the data
managed in multiple files. Used to manage
employee lists, student list letters, etc. E.g.
Microsoft Access, dBase, SQL Server
34Packaged Software
Graphics Allows a person to present information
in the form of charts and graphics or to create
complex freehand artwork. Used for
presentations. Simple graphics are provided by
spreadsheet software, while others are more
sophisticated s/w. E.g. Microsoft PowerPoint,
Adobe Illustrator
35Packaged Software
Communications Allows a person to manage the
transformation of data between computers over
wired or wireless channels. Used for E-mail,
Internet, FTP, etc. E.g. ProComm, Smartcom,
Crosstalk
36Customised Software
Accounting, Sales and Distribution,
Manufacturing, Management Sciences, Medical and
Health Care, Real Estate, Personal Investor, Tax
Manager, Time Scheduler, etc. e.g.
ACCOUNTING Inventory Control Accounts
Receivable Payroll General Ledger
37Evolution of Computers
- 1st Generation Computers
- 2nd Generation Computers
- 3rd Generation Computers
- 4th Generation Computers
38First Generation (1951-58)
- Vacuum tubes for internal operations
- Low-Level languages for programming (machine
language)
39First Generation (1951-58)
- Magnetic drums for primary memory.
- Primary memory limited.
- Heat and maintenance problems.
- Punch cards for input and outputs.
- Slow input and output
- e.g. UNIVAC I, EDVAC
40Second Generation (1958-64)
- Transistors for internal operations.
- Increased use of high level languages.
- Magnetic cores for primary memory.
- Increased memory capacity.
- Binary coded data.
- Increasing processing speed.
- Magnetic tapes and disks for secondary storage
- e.g. IBM 1620, UNIVAC 1108.
41Third Generation (1965-70)
- Integrated circuits (ICs) on silicon chips for
internal operations. - Increased memory capacity.
- Common use of minicomputers.
- Emergence of software industry.
- Reduction in size and cost.
- Increase in speed and reliability.
- e.g. HONEY WELL-6000 SERIES
42Fourth Generation (1971-today)
- Large Scale Integration (LSI) and Very Large
Scale Integration (VLSI) for internal operations. - Development of the microprocessor.
43Fourth Generation (1971-today)
- Introductions of micro and super computers.
- Increase in speed,power and storage capacity.
- Parallel processing.
- Artificial intelligence and expert systems.
- Robotics
- Increased use of Micro/Personal Computers.
- e.g. Apple II, IBM PC, Micro Computers
44Fifth Generation (1981-1990s)
- A project to develop intelligent computers.
- They are computers with artificial intelligence.
- Symbolic manipulation and symbolic reasoning is
required.
45Classification of Computers
- Mainframe Computers.
- Minicomputers.
- Microcomputers.
- Special Purpose Computers.
46Types of Modern Computers
- Microcomputers
- Workstations and Personal Computers
- Minicomputers
- Mainframe Computers
- Parallel Processing Computers
- Supercomputers
47Microcomputers
- Based on a microprocessor - single silicon chip
CPU. - Enables the integration of sound, video,
graphics, as well as text into software - 'Multi-media' systems now available.
48Microcomputers
- Appeared mid-to-late 70s.
- E.g. Apple II, TRS-80, Sinclair Spectrum,
Commodore PET - Peripherals connected via ISA, PCI, EISA,
PCMCIA/PC Card e.g. CD-ROM sound card, speakers,
microphone - Portable models now available
49Microcomputers
- Small computers that can fit on a desktop or
briefcase. - Two types
- Personal Computers (PC)
- Workstations
50Personal Computer (PC)
- Desktop or portable (laptop, notebook, palmtop).
- Used in most organisations and at homes.
- Commonly used for easy-to-use programs such as
word processing, spreadsheets.
51Workstations
- Powerful and expensive than a PC.
- Often connected to large computer system.
- Designed to work with large or complex
applications. - Used by engineers and scientists.
- e.g. drafting, engineering design, 3D-graphical
models
52Minicomputers
- Scaled down mainframe. (refrigerator-size)
- Designed to meet the computing needs of a
department or small company. Typically 4-100
concurrent users.
53Minicomputers
- Usually run without a special environment.
- Can support a number of concurrent applications
and often uses a time-sharing operation system
that aims to keep the users busy.
54Minicomputers
- Lesser processing speed and data-storing
capabilities than mainframes and used by
medium-sized companies for specific purposes. - Low-end mainframes and high-end microcomputers
can overlap.
55Mainframe Computers
- A multi-user computer designed to meet the
computing needs of a large organization. - Originally the term referred to the metal cabinet
housing the CPU. - Generally refers to computers of the 1950s and
1960s.
56Mainframe Computers
- A Large number of dumb terminals were used for
input/output and it had a large number of
peripherals attached.
57Mainframe Computers
- Can process a number of applications
concurrently. - Used by large organisations to handle millions of
transactions. - Usually housed in specially wired air-conditioned
rooms. - Less powerful than supercomputers.
58Supercomputers
- Sophisticated, expensive computers, using
state-of-the-art technology. - Provide processing speeds, many times that of
powerful workstations. - Particularly used in the simulation and modeling
of complex systems. - e.g. weather, chemical processes, the US economy,
motion of galaxy
59Evolution of Intel Microprocessors
60Evolution of Intel Microprocessors
61Questions ????