Fundamentals of Information Systems: Media A. Ibrahim MSC: Software Engineering Ise Department
Fundamentals of Information Systems: Media A. Ibrahim MSC: Software Engineering Ise Department
Fundamentals of Information Systems: Media A. Ibrahim MSC: Software Engineering Ise Department
Media A. Ibrahim
MSc: Software Engineering
ISE Department
Media.ibrahim@epu.edu.krd
2019-2020
1
Defining information systems(technology)
2
Outlines
• Computer Hardware
• Central Processing unit(CPU)
• Primary storage (main memory; memory)
• Secondary storage
• Input devices
• Output devices
3
Computer Hardware
Hardware describes the physical components of a computer system, which
can be categories as Input devices, output devices, memory and Central
processing unit, etc.
Hardware Components
in Action
• Step 1: Fetch instruction
• Step 2: Decode instruction
• Step 3: Execute the instruction
• Step 4: Store results
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CPU
CPU is the abbreviation for central processing unit.
Sometimes referred to simply as the central processor, but
more commonly called processor, the CPU is the brains
of the computer where most calculations take place. In
terms of computing power, the CPU is the most important
element of a computer system.
Converts data into information
Reading instructions from RAM and executing them
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Components of CPU
The CPU Consists of:
–Control Unit
–Arithmetic Logic Unit (ALU)
–Registers (high-speed memory)
•Program Counter (PC)
•Instruction Register (IR)
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Arithmetic / Logic Unit
ALU
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Arithmetic Operations
Addition
Subtraction
Multiplication
Division
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Logical Operations
• Evaluates conditions
• Makes comparisons
• Can compare
– Numbers
– Letters
– Special characters
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Registers
Registers
– The CPU contain special storage areas called registers.
– Their function is to hold instructions, data values, memory
addresses of both the instructions and data.
There are 4 basic types of it:
1. Instruction register hold instruction
2. Address register hold address of( data , next instruction ).
3. Storage register store data retrieved from main memory
prior to processing.
4. Accumulator store the results of arithmetic & logic
operations
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Memory Characteristics and Functions
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Storage Capacity
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Types of Memory
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Types of Memory(Continued…)
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Types of Memory(Continued…)
Types of ROM
ROM (read-only memory)
PROM (programmable read-only memory)
EPROM (erasable programmable read-only memory)
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Difference Between RAM & ROM
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Secondary Storage
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Secondary Storage (Continued..)
Access Methods
Data and information can be retrieved from secondary storage in two main
ways. Access can be either sequential or direct.
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Classification of Commonly Used Secondary Storage Devices
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Outlines
• Computer Software
o System software
• Operating Systems
• Utility Programs
• Software development programs.
o `Application Software
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Computer Software
• Software can be defined as a series of detailed
instruction that control the operation of a computer
system and exists as programs which are developed
by computer programmers.
• Some of the personal tasks that can be done by
using software are:
– Internet research
– Games
– Keeping a budget
– Income tax preparation
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Computer Software(cont.)
There are two major categories of software:
1. System software
2. application software
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System software
• System Software is an interface between users,
application software and hardware.
• Generalized programs that manage the computer’s
resources, such as the central processor,
communications links, and peripheral devices.
• .The main role of System Software is to communicate
with hardware.
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System software(cont.)
• System Software consists of:
– Operating Systems
– Utility Programs
– Software development programs.
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Operating System
• Operating System is a software, which makes a computer to
actually work.
• The operating system is a program that is always running on
the computer.
Mainframe
DOS
OS/2
Linux
Mac OS
What the Operating System Does
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Operating System (cont.)
Types of Operating System:
Single-tasking
DOS
Multi-tasking
Windows 8
Mac OS
UNIX
Network Operating Systems:
NetWare
UNIX
Window Server
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Utility Programs
• Utility programs help to manage, maintain and
control computer resources.
• Examples of Utility programs:
– Backup software
– Scandisk
– Virus scanning software
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Software development programs
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Application Software
• Application software helps users to solve a particular
problem.
• It consists of programs that direct computers to
perform specific information processing activities for
end users.
• Application software can also e stored on CDs ,
DVDs, and flash
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Application Software(cont.)
• Types of Application Software are:
Word Processing Software
Spread sheet Software
Presentation Software
Database Software
Multimedia Software
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Conclusion
• Hardware and software are two important
components of IS.
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