computer fundmental
TRANSCRIPT
UNESCO ICTLIP Module 1. Lesson 4. 1
Midnimo Group Deeqo C/qaadir Ibraahim Ayaan C/qaadir Xasan Ikraam C/qaadir Jimcaale Faadumo Daahir
C/Raxmaan
UNESCO ICTLIP Module 1. Lesson 4. 2
Outlines What is computer? Hardware Software Central Processor Unit (CPU)
UNESCO ICTLIP Module 1. Lesson 4. 3
What Is a Computer? A computer is an electronic device, operating under
the control of instructions stored in its own memory
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Information Processing Cycle
The Components of a Computer A computer contains many electric, electronic, and
mechanical components known as hardware
Pages 6 - 8
The Components of a Computer
Page 7 Figure 1-3
Storage DevicesStorage Devices
Hard Disk Hard Disk
Flash Drive Flash Drive
CD-ROM CD-ROM
DVD-ROM DVD-ROM
Parts of a Computer Input DevicesParts of a Computer Input Devices
MouseMouse
KeyboardKeyboard
MicrophoneMicrophone
ScannerScanner
WebcamWebcam
Parts of a Computer Output Parts of a Computer Output DevicesDevices
Monitor
Printer
Speaker/Headphone
Advantages and Disadvantages
of Using ComputersAdvantages of
Using ComputersDisadvantages of Using Computers
Pages 9 - 10
Categories of Computers
Page 19
Personal Computers A personal computer can perform all of its input,
processing, output, and storage activities by itself Two popular architectures are the PC and the Apple
Desktop computer
Page 19 Figures 1-15 - 1-16
Mobile Computers and Mobile Devices
Pages 20 - 23
Mobile Computers and Mobile Devices
Pages 20 - 22 Figures 1-17 – 1-20
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Mobile Computers and Mobile Devices
Pages 22 - 23Figures 1-21 – 1-23
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Mainframes A mainframe is a
large, expensive, powerful computer that can handle hundreds or thousands of connected users simultaneously
Page 25 Figure 1-26
Super computers A supercomputer is the fastest, most powerful
computer Fastest supercomputers are capable of processing
more than one quadrillion instructions in a single second
kPage 25 Figure 1-27
Medicine. Nuclear Energy Online Banking Weather Forecasting
Computer Applications in Society
, Pages 34 - 36 Figures 1-36 – 1-39
Computer Applications in Society
Pages 36 - 38Figures 1-40 – 1-43
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Welcome to Ayaan She is Explaining Hardwar
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HARDWARE HARDWARE is the collection of
physical elements that constitute a computer system.
Basic hardware of a PC system Central Processing Unit (CPU) Memory Unit Input Devices Output Devices Secondary Storage Devices
1. Central Processing Unit
Brain of the computer. It directs and controls the entire computer
system and performs all arithmetic and logical operations.
2. Memory Unit Where the programs and data
are stored . READ ONLY MEMORY (ROM)
contains the pre-programmed computer instructions such as the Basic Input Output System (BIOS).
RANDOM ACCESS MEMORY (RAM) is used to store the programs and data that you will run. Exists only when there is power.
3. Input Devices Allows data and programs to be sent to the
CPU. Keyboard Mouse Joystick Microphone Webcam Scanner Monitor
THE KEYBOARD
The keyboard was one of the first peripherals to be used with computers, and it is still the primary input device for entering text and numbers. A standard keyboard includes about 100 keys; each key sends a different signal to the CPU.
Numeric keys Function keys
Space bar Arrow keys
Shi
ft ke
yC
aps
lock
Esca
pe
Control keyENTER KEY
TAB KEY
ALT (Alternate) key
Backspace
ALPHABET KEYS
Shortcut keyStart key
Two Types of Mouse Mechanical - a type of
computer mouse that has a rubber or metal ball on its underside and it can roll in every direction.
Optical: This type uses a laser for detecting the mouse's movement.
Scanning Devices Optical scanners Card readers Bar code readers Character and mark recognition
devices
4. Output Devices Media used by the computer in
displaying its responses to our requests and instructions.
Monitor Audio Speakers Printer
Types of Monitor Cathode Ray Tube (CRT)
Liquid Crystal Display (LCD)
Printers IMPACT PRINTERS uses pressure by physically
striking the paper. Ex. Daisy wheel printers, line printers, dot matrix printers & band printers.
NON-IMPACT PRINTER does not apply pressure on the paper but instead produces character by using lasers, ink spray, photography or heat.
Dot matrix printer
Inkjet printerLaser printer
5. Secondary Storage Devices Attached to the computer system
to allow you to store programs and data permanently for the purpose of retrieving them for future use.
Floppy disk, Hard disk, CD Rom
Floppy Disk The most common secondary
storage device 3.5” disk – 1.44MB
Hard Disk Drive or Hard Disk
Made of rigid materials unlike floppy disks Holds a greater amount of data
10MB in 1980s 600MB in mid 1990s 4.3GB in 1999 180GB in 2001 400GB - 2004
Optical Discs A standard part of modern desktop
machines, especially used for multimedia purposes and preferred in loading applications.
Parts that Build Up A System Unit
Casing or cover
Power Supply Motherboard Microprocessor Memory Video Card
Sound card Floppy disk
drive Hard disk drive CD-ROM drive MODEM
Casing or cover. Protects the computer
circuits, cooling and system organization.
Power Supply Responsible for powering every device in your
computer. Parts of a Power supply:
Disk drive connectors Motherboard connector Power supply fan Power switch Input voltage selector Cover Power plugs receptacle
Motherboard The physical arrangement in a computer that
contains the computer’s basic circuitry and components.
Components are: Microprocessor (Optional) Coprocessors Memory Basic Input/Output System (BIOS) Expansion Slot Interconnecting circuitry
Expansion Slots Graphic cards Sound cards Modem cards Network interface cards/network
adapter
Welcome to Ikraam She is Explaining Softwar
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SOFTWARE
Programs written in a special language with a series of instructions to a computer or its peripherals that cause the computer to solve a problem or perform a task to achieve a specific set of results.
Simply a set of instruction necessary for a computer to accomplish required tasks.
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Software Software make up the set of
instructions for the computer. Without software, the computer will not be able to perform the tasks that you would like it to do.
Operating System controls all machine activities provides the user interface to the computer manages resources such as the CPU and memory DOS, Windows XP, Unix, Linux, Mac OS
Application program generic term for any other kind of software
(custom made) MS Word, MS Excel, Games,….. Library
softwares e.g, Koha, WINISIS, LIMS, LAMP….
TYPES OF SOFTWARE
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Operating system An organized collection of system programs
which serve as the interface between the user or application and the computer.
It manages the hardware resources: CPU management to facilitate sharing
execution time of processes Memory management to allocate memory
resources dynamically I/O management to handle reading and
writing devices
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Disk Operating Systems (DOS)
Disk Operating System (DOS) is a generic term describing any operating system that is loaded from disk devices when the system is started or rebooted.
It is not a user friendly OS since users need to memorize commands and issue it by typing line by line. This known as command line interface. Very few end users use DOS nowadays.
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Microsoft Windows A graphical user interface (GUI) originally
running on DOS (Windows 3.x) that allows multitasking or the ability to run several programs at the same time.
Windows 95 / Windows NT that no longer runs on DOS
About 75% of the world’s PCs use the Windows operating system. The present versions in use are Windows 98, Windows Me and Windows 2000.
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Other operating systems
IBM OS/2 Macintosh OS SCO Unix Linux Other Proprietary OS
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Applications software
A set of instructions designed to perform a specific task such as word processing, accounting, cataloguing, library management, animation, etc.
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Types of applications software
The nature of the software depends on the application General purpose office software Business management software Special discipline software Other applications
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General purpose office software Word processing: Example, MS Word Spreadsheets: Example, Excel Database management systems:
Example, MS Access, Oracle Presentation/Graphics: Example,
Power Point, Corel
Welcome to Faadumo She is Explaining CPU (Centeral Processing Unit)
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Processor
What is processing ?
The processor is the brain of the PC sometimes called microprocessor or CPU (Central Processing Unit)
Converts data into in formation Control center Set of electronic circuitry that executes stored
program instruction The CPU performs the system's calculating and
processing
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Cont….. The processor and the main memory devices are
the intelligence of the computer. Housed by the system unit, the processor also known as the CPU (central processing unit) interprets and executes instructions while the main memory serves as the computer's "work space". The processing power of a computer largely depends on the speed of the processor and size of its main memory. Faster processor results to faster execution of instructions.
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Processor
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Cont.
The processor is often the most expensive single component in the system.
A central processing unit (CPU) is the electronic circuitry within a computer that carries out the instructions of a computer program by performing the basic arithmetic, logical, control and input/output (I/O) operations specified by the instructions.
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Cont…..The form, design and implementation of CPUs
have changed over the course of their history, but their fundamental operation remains almost unchanged.
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cont….Principal components of a CPU include the arithmetic
logic unit (ALU) that performs arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that fetches instructions from memory and "executes" them by directing the coordinated operations of the ALU, registers and other components.
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OperationThe fundamental operation of most CPUs, regardless of the physical form they take, is to execute a sequence of stored instructions that is called a program. The instructions to be executed are kept in some kind of computer memory.Nearly all CPUs follow the fetch, decode and execute steps in their operation, which are collectively known as the instruction cycle.
After the execution of an instruction, the entire process repeats with the next instruction cycle normally fetching the next-in-sequence instruction because of the incremented value in the program counter.
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Fetch The first step fetch involves retrieving
an instruction (which is represented by a number or sequence of numbers) from program memory.
The instruction's location (address) in program memory is determined by a program counter (PC), which stores a number that identifies the address of the next instruction to be fetched.
After an instruction is fetched, the PC is incremented by the length of the instruction so that it will contain the address of the next instruction in the sequence.
Decode The instruction that the CPU fetches from memory
determines what the CPU will do. In the decode step, performed by the circuitry
known as the instruction decoder, the instruction is converted into signals that control other parts of the CPU.
The way in which the instruction is interpreted is defined by the CPU's instruction set architecture (ISA).
Execute After the fetch and decode steps, the execute step
is performed. Depending on the CPU architecture, this may
consist of a single action or a sequence of actions. During each action, various parts of the CPU are
electrically connected so they can perform all or part of the desired operation and then the action is completed, typically in response to a clock pulse.
Very often the results are written to an internal CPU register for quick access by subsequent instructions.
Cont.
In other cases results may be written to slower, but less expensive and higher capacity main memory.
For example, if an addition instruction is to be executed, the arithmetic logic unit (ALU) inputs are connected to a pair of operand sources (numbers to be summed), the ALU is configured to perform an addition operation so that the sum of its operand inputs will appear at its output, and the ALU output is connected to storage (e.g., a register or memory) that will receive the sum.
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Control unit
Part of the hardware that is in-charge. Directs the computer system to execute stored
program instructions. Communicates with other parts of the hardware. The control unit of the CPU contains circuitry
that uses electrical signals to direct the entire computer system to carry out stored program instructions.
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Arithmetic logic unit
Performs arithmetic operationsPerforms logical operationsThe arithmetic logic unit (ALU) is a digital circuit within the processor that performs integer arithmetic and bitwise logic operations. Depending on the instruction being executed, the operands may come from internal or external memory, or they may be constants generated by the ALU itself.
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Cont….. The result consists of both a data word,
which may be stored in a register or memory, and status information that is typically stored in a special, internal CPU register reserved for this purpose.
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Arithmetic Operations
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Logical Operations
Thank you for you listening
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