week4-measuring data

1. MEASURING DATA BITS AND BYTES

2. Understanding Data Data (the plural of datum ) are anything in a form suitable for use with a computer . Whatever a computer receives as an input is data. Data are raw facts without any clear meaning. Computers process data and generate information . All data stored and processed by computers are in the form of whole numbers . The purpose of the numbers becomes clear after they are interpreted and displayed by software.

3. Part of the data stored in the computer for the file apple.bmp The apple.bmp File

4. Decimal Number System

5. Binary Number System

6. Bits and Bytes We measure computer information (data) in bits and bytes. Bit is short for binary digit . It is the smallest unit of information that a computer can understand . One bit represents a 1 or digit in a binary numeral or a true or false logical condition. A bit is represented physically by high or low voltage in a circuit or a small magnetized spot on a disk.

7. Bits and Bytes Byte is short for binary term . A byte usually contains eight bits. It can represent a single character, such as a letter, a digit, or a punctuation mark . Because a byte represents only a small amount of information, we usually measure amounts of computer memory and storage in kilobytes (one kilobyte is 1024 bytes), megabytes (one megabyte is 1048576 bytes ), gigabytes (one gigabyte is 1073741824 bytes).

8. Bits and Bytes In Bytes In Bits (Power Notation) In Bits 1 byte 2 3 bits 8 bits 1 kilobyte   (KB ) 2 10 bytes 1024 bytes 1 megabyte  (MB) 2 20 bytes 1024 kilobyte s 1 gigabyte  (GB) 2 30 bytes 1024 megabyte s 1 terabyte  (TB) 2 40 bytes 1024 gigabyte s 1 petabyte  (PB) 2 50 bytes 1024 terabyte s 1 exabyte  (EB) 2 60 bytes 1024 petabyte s 1 zettabyte  (ZB) 2 70 bytes 1024 exabyte s 1 yottabyte  (YB) 2 80 bytes 1024 zettabyte s

9. Binary, Decimal and Hexadecimal Numbers

10. 512 MB = ……………...…....… GB 64 b = …………........……… B 5120 GB = ………....……...…… TB 4096 PB = …….....………...…… EB 0.25 GB = .......………………… MB

11. TAKING CARE OF THE COMPUTER

12. Monitor Cleaning

13. Keyboard Cleaning

14. Mouse Cleaning

15. Case Cleaning

16. Keep Your PC Cool Buy Quality Hardware Get Power Protection Get an Anti-Virus Program Scan for Other Malware Run the Defragmenter Utility Clean Up Old Files

17. HEALTHY COMPUTER USE Make Yourself Comfortable Put the computer directly in front of you when you work. Make sure you have enough space to operate the different parts of the computer (keyboard , mouse , etc.) easily. Set your chair height so that the keyboard is at (or slightly below ) the level of your elbow . You should be able to type comfortably with your shoulders relaxed.

18. HEALTHY COMPUTER USE Make Yourself Comfortable Set the back of your chair so that it supports the lower part of your spine. Sit straight so that your knees , hips, and elbows are at about 90 degree angles when you work. Do not lean forward or back too far .

19. HEALTHY COMPUTER USE Take a Break Change your position often. If you use a computer for a long time, stand up and stretch your wrists, hands, and legs regularly . Take frequent short breaks (for example, two or three minutes every half hour ) instead of one or two long breaks.

20. BUYING A COMPUTER Your Needs Windows vs. Mac Desktop vs. Laptop Hardware Software Service, Support and Warranty