1. Course Introduction & Computer Hardware Second Career Computers Fall 2009

2. 2 Objectives Discuss reasons for taking this course on computers Outline the scope of this course Define the computer Differentiate between hardware and software Parts of the Computer: –Describe the main hardware components –Explain how computers work –Describe how information is stored –Care for external storage devices (CDs, DVDs and Memory Keys)

3. 3 What are the many ways that you use computers today? Reasons for taking this course

4. 4 Computers are everywhere. We use them for home, school and work. They play a crucial role in our lives and society. Thus it is important to have a good understanding of computers.

5. 5 Scope of this Course Computer Hardware Computer Software File Management Internet Email MS Word MS PowerPoint MS Excel

6. 6 Definition of the Computer How is a computer defined? Electronic machine operating under the control of instructions stored in its own memory Accepts data Manipulates data Produces results Stores results

7. 7 What does it consists of ? Software Instructions that tell hardware how to perform tasks Hardware Physical Equipment (Electronic and mechanical equipment) Definition of the Computer

8. 8 What are the main computer parts or hardware? Parts of the Computer CPU MemoryInput Storage Output Data Flow Control

9. 9 Parts of the Computer What are the input components? scanner microphone keyboard PC camera digital camera Hardware used to enter data and instructions Turns information into a series of electronic pulses that the computer can understand. mouse

10. 10 Parts of the Computer What are the output components? Hardware that conveys information to a user The series of electronic pulses are passed from the CPU and turned into something that we can see and/or hear through the output devices. printer monitorspeakers

11. 11 processor (RAM) memory modules Parts of the Computer Where is the CPU or Central Processing Unit? It is contained in the systems unit. Box-like device containing electronic components connected to motherboard. Systems Unit

12. 12 processor hard disk CD or DVD drive (RAM) memory modules USB drive Brains of the Computer! Parts of the Computer What is the CPU or Central Processing Unit? Hardware used to process the data & instructions. Carries out instructions that tells the computer what to do

13. 13 processor Parts of the Computer How does the CPU work? 1. Receives the series of electronic pulses or information from the input unit and memory unit (e.g., keyboard, RAM, hard drive, etc). 2. Processes it. 3. Sends the processed information to the memory and/or to the output unit. Steps: CPU Memory Storage Output Data Flow Control Input

14. 14 Parts of the Computer What is the memory? Stores the instructions or information that the computer is currently working on or that will be needed later. Two types of memory: ExternalInternal

15. 15 Parts of the Computer What is the internal memory? –Internal memory is usually not large enough to hold all the information needed. –It is usually not as portable unless you can take your computer with you. Types of internal memory: ROM Read Only Memory RAM Random Access Memory TemporaryPermanent

16. 16 Parts of the Computer What is external memory or storage? –External memory can be permanent. Some types of memory units are only permanent until they are modified or deleted. –Some memory units are portable. For example: You can take CDs, DVDs and USB Flash Memory Keys with you to use on another computer. However, you cannot take your hard disk drive in your systems unit with you. Hard Disk Drive (inside case) CD Drive USB Flash Memory Drive DVD Drive Systems Unit

17. 17 What is a USB flash memory key? It is a thin, rectangular, key sized object that is enclosed in metal and/or rigid plastic. It plugs into your USB drive on a computer. It can read and write information. It can hold from 1 to several gigabytes (GB) of information. It stores and retrieves information very quickly. p. 1.7 Fig. 1-5 Next Parts of the Computer External memory or storage

18. 18 How do you care for a flash memory key? Parts of the Computer 1: Store in a safe place where you can find it. (e.g., in purse or wallet, pen case, or on a strap) 2. Do not forget to take out it in the computer when you leave the room. 3. Follow the steps below to remove it safely from a computer: - Click on the “Safely Remove Hardware” icon on the bottom right side of your screen. - In the “Safely Remove Hardware” dialog box, click the “Stop” button. - Make sure that the “USB Mass Storage Device” is highlighted. - Click the “OK” button. - Click the “Close” button. 4. Keep the end cap on the key when it is not in use.

19. 19 What is a CD or DVD? Portable storage media Compact Disks: – CD-R (Recordable) – CD-RW (Rewritable) Digital Video Discs: – DVD-ROM (Read Only Memory) – DVD+RW (Rewritable) p. 1.8 Fig. 1-8 Next Parts of the Computer External memory or storage

20. 20 p. 7.8 Fig. 7-8 How does a disc store information? It stores information in tracks and sectors. Track is narrow recording band that forms full circle on disk surface Sector can store up to 512 bytes of data Next sector 18 per track track 80 per side 80 tracks per side X 18 sectors per track X 2 sides per disk X 512 bytes per sector = 1,474,560 bytes Parts of the Computer External memory or storage

21. 21 What is a hard disk? Provides much greater storage capacity than a CD, DVD or Flash Memory Key Reads and writes information on non-removable disks. Holds a great deal of information (e.g., many gigabytes GB). removable hard disk self-contained hard disk p. 1.7 Fig. 1-6 & 7 Next Parts of the Computer External memory or storage KB = exactly 1,024 bytes MB = one million bytes GB = one billion bytes (1000 times a MB)

22. 22 1.How is a computer defined? 2.What are the main computer parts or hardware? 3.What are the two types of internal memory? 4.How is information stored on a USB Memory Key? 5.How is information stored on a CD? Parts of the Computer/Hardware Summary