1. Introduction to Computers

2. Outline Basic Organization of Computer: Input Unit Output Unit
Memory Unit
Control Unit
Arithmetic & Logic Unit (ALU)
CPU = ALU + CU

3. Organization
CPU
Input Unit
Output Unit
ALU
Control Unit
Memory Unit

4. Inside the Computer

5. Input unit
Trough input devices command/problem/ instructions are passed to the CPU.
Command as Electric signal moves to CPU or Preserved in the memory for further execution

6. Input unit Examples: Keyboard Mouse Scanner OMR OCR MICR
Barcode reader
Microphone
Joystick
Digital Camera
Light Pen
Track Ball
Card reader
Punch card
Webcam

7. Output unit
Processed data or result is displayed in an understable way through output unit
Example:
Monitor
Printer
Speaker
Plotter
Microfilm, etc
There are two types of output-
Hard copy:
Printed papers, can be carried, touches
Soft copy:
Result displayed in the monitor, can be viewed

8. CPU Most important part of computer Known as the “Brain of computer”
CPU is used for processing data & problems
All types of calculation and decision making is done by CPU
Collects the data from input, prepare result as per command and shows output

9. CPU There are two main units of CPU, Arithmetic & Logic Unit (ALU)
Control unit (CU)

10. ALU Known as `Arithmetic Logic Unit` Solves all types of problems
Data analysis
All types of calculation like Addition, Subtraction, Multiplication, Division following the “Binary Rule”
Perform logical operations Like: AND OR NOT, >, >=, <, <=, <> etc

11. Control unit Controls & balances all the activities of the Computer
Control the computer as per instructions like Data input, When/Where/How it will go? etc. are determined by control unit
Transfers control to the next instruction
Controls all the Hardware & software
Determine` where the next instruction is located? & How it will be executed?`

12. Memory unit RAM, ROM Hard disk, Floppy disk, Optical Disk,
One of the most important part of computer that preserves data, instructions,results etc
Examples:
RAM, ROM
Hard disk, Floppy disk, Optical Disk,
Cache, Virtual Memory etc
There are three types of memory-
01. Processor Memory
02. Primary Memory
03. Secondary Memory

13. Processor Memory Also known as `Built-in Memory`
There are some `Registers` in the ALU whose acts as processor memory
Used as a working memory of temporary storage of instructions & data
Another built in memory to support resisters is called `CACHE`

14. Primary memory Also known as `Main memory`
The memory in which CPU access directly & rapidly is called primary memory
When any programme runs the CPU has a direct access with memory for processing
Technology based on `SEMICONDUCTOR`
Example:
RAM
ROM

15. Secondary memory Also known as Auxiliary Memory, permanent
Only stores data & system program
Generally two types:
Magnetic:
HDD, FDD, Magnetic disk, Magnetic tape etc
Optical:
CD-ROM/DVD-ROM, Optical disk etc