1. Introduction to Computing Lecture # 1

2. Outline The Computer Defined How Computer Works: 3 Basic Concepts
Role of Software

3. The Computer Defined
“Electronic device for storing and processing data, making calculations, or controlling machinery.” (The Pocket Oxford Dictionary)
“An electronic device that processes data, converting it into information that is useful to people.” (Peter Norton)
“A programmable, multiuse machine that accepts data – raw facts and figures – and processes, or manipulates, it into information we can use.” (Williams and Sawyer)

4. What’s so special about computer?
What makes computer different from other machines is that:
Computer
runs program!
By changing the program (instructions), the same computer can be used to perform different function

5. How Computers Work – Concept # 1
The purpose of computer is to process data into information
Data
The raw facts and figures that are processed into information
Information
Data that has been summarized or otherwise manipulated for use in decision making
Teaching tip
A good exercise to relate the importance of making data meaningful is to list some random numbers on the board. Then ask what they mean. Without a title, the numbers have no meaning. Once a title is presented, the numbers make sense.

6. How Computers Work – Concept # 2
Computers consist of hardware and software
Hardware
All the machinery and equipment in a computer system
Mechanical devices in the computer
Anything that can be touched
Software
All the instructions that tell the computer how to perform a task
Tell the computer what to do
Also called a program
Thousands of programs exist

7. How Computers Work – Concept # 3
All computers follow same basic operations.
Input
Processing
Output
Storage
Communication (optional)
Teaching tip
It is helpful to walk through a simple program to demonstrate the cycle. I often use a simple arithmetic problem to show this cycle.

8. How Computers Work – Concept # 3
1. Input
Input - whatever is put into (“input”) a computer system.
Input hardware - devices that allow people to put data into the computer in a form that the computer can use.
Mouse - an input device that is used to manipulate objects viewed on the computer display screen.
Keyboard - an input device that converts letters, numbers, and other characters into electrical signals readable by the processor.
Keyboard
Mouse

9. How Computers Work – Concept # 3
2. Processing
Processing - the manipulation a computer does to transform data into information.
Case or system cabinet - the box that houses the processor chip (CPU), the memory chips, and the motherboard with power supply, as well as some secondary storage devices.
Case or system cabinet

10. How Computers Work – Concept # 3
2. Processing
Processor chip - A tiny piece of silicon that contains millions of miniature electronic circuits.
Is like the brain of the computer
Carries out instructions from the program
Manipulate the data
Most computers have several processors
Central Processing Unit (CPU)
Processor chips

11. How Computers Work – Concept # 3
2. Processing
Memory chips
Also known as RAM (Random Access Memory).
Represent primary storage or temporary storage.
Hold data before processing and information after processing.
Also stores program instructions
Volatile
More RAM results in a faster system
Memory chips

12. How Computers Work – Concept # 3
2. Processing
Motherboard - the main circuit board in the computer.
Everything else attaches to the motherboard through connections called ports.
Expansion slots - “plugs” on the motherboard for expanding the PC’s capabilities via additional circuit boards.
Motherboard

13. How Computers Work – Concept # 3
3. Storage
Primary storage (memory) - RAM
Computer circuitry that temporarily holds data waiting to be processed
vs.
Secondary storage (storage) -
The area in the computer where data or information is held permanently
Storage capacity is represented in:
1 byte - 1 character of data.
1 kilobyte - 1,024 characters.
1 megabyte - 1,048,576 characters.
1 gigabyte - more than 1 billion characters.
1 terabyte - more than 1 trillion characters.

14. How Computers Work – Concept # 3
3. Storage
Floppy-disk drive - a storage device that stores data on removable 3.5-inch-diameter diskettes.
Zip-disk drive - a storage device that stores data on floppy-disk cartridges with times the capacity of the standard floppy.
Floppy disk
Zip disk

15. How Computers Work – Concept # 3
3. Storage
Hard-disk drive - a storage device that stores billions of characters of data on a non-removable disk platter.
Magnetic storage (Floppy and hard drive) uses a magnet to access data.
Hard-disk drive

16. How Computers Work – Concept # 3
3. Storage
CD (Compact Disk) drive or DVD (Digital Video Disk) drive - a storage device that uses laser technology to read data from optical disks.
Optical storage
CD drive

17. How Computers Work – Concept # 3
3. Storage
Flash Memory and USB Drive
Stores data by turning million of tiny switches on and off.
Flash Memory
and USB Drive

18. How Computers Work – Concept # 3
4. Output
Output hardware - devices which translate info processed by the computer into a form that humans can understand.
Peripheral device - any component or piece of equipment that expands a computer’s input, storage, and output capabilities.
Sound card - enhances the computer’s sound-generating capabilities by allowing sound to be output through speakers.
Sound card

19. How Computers Work – Concept # 3
4. Output
Speakers - the devices that play sounds transmitted as electrical signals from the sound card.
Speakers

20. How Computers Work – Concept # 3
4. Output
Video card - converts the processor’s output information into a video signal that can be sent through a cable to the monitor.

21. How Computers Work – Concept # 3
4. Output
Monitor - the display device that takes the electrical signals from the video card and forms an image using points of colored light on the screen.
Monitor

22. How Computers Work – Concept # 3
4. Output
Printer - an output device that produces text and graphics on paper.
Printer

23. How Computers Work – Concept # 3
5. Communications
Modem - a device that sends and receives data over telephone lines to and from computers.

24. Put all the hardware together and…

25. Do we need anything else?
We still need the
Software!

26. Software Runs The Machine
The majority of people who purchase computers, do so, because of software.
They want to , or type letters.
Nearly every reason given to purchase a computer is based on software needs.
Software tells the computer what to do
Two types
System software
Application software

27. Software Runs The Machine
System software
Helps the computer perform essential operating tasks and enables the application software to run
The Resource Manager
and…

28. Software Runs The Machine
Application software
Enables you to perform specific tasks. e.g:
Word Processing
Photo Editing
Creating web pages
Computer Games…