1. How We Measure Memory

2. Learning Goal Today we are going to learn how the computer stores information.

3. At the Bottom of things A piece of digital information is always stored as a sequence of binary states. What is a “binary state”???

4. A microscopic view of a CD

5. Electrical Memory RAM, Memory Sticks, Memory Cards all store information as sequences of negative or neutral charges. The two states are negative and Neutral

6. A “bit” A bit of information is a single binary state. For example: “on” or “off” “pit” or “land” “negative” or “neutral” “dead or “alive”

7. “A Byte” There are 8 bits in a byte. A byte can hold a single character. Ex: ‘A’

8. A “Kilobyte” (Kb) A Kilobyte is 1024 bytes or 2 10. (or about 1000 bytes) You would measure an Email in Kb.

9. A Megabyte Mb A megabyte is 1 048 576 bytes which is 2 20. (Or about 1 million Bytes) Mp3s and digital pictures are usually 2-5 Mbs.

10. Gigabytes (Gb) A Gigabyte is 1 073 741 824 bytes or 2 30 or about 1 billion bytes. We measure RAM, Hard drives, Memory cards in Gb.

11. Terabyte A Terabyte is 2 40 which is 1 099 511 627 776 bytes Large hard drives are measured in Terabytes.

12. Beyond Terabytes?? Chart from Wikipedia.

13. Summary 1.A bit is a single binary state. 2.There are 8 bits in a byte 3.There are about 1 000 bytes in a Kilobyte. 4.There are about 1 000 Kilobytes in a Megabyte 5.There are about 1 000 Megabytes in a Gigabyte 6.There are about 1 000 Gigabytes in a Terabyte