Answers to Ch. 6 Questions

1. Nonvolatile storage is storage that is permanent.

2. We need external storage because computer users typically need more space than is available on the computer's primary of RAM memory.

3. Secondary storage is a permanent storage place.

4. Writing means saving information to a secondary storage device

5. Reading is assessing the info that is stored on a secondary storage device.

6. The 4 most widely used forms of secondary storage are floppy disks, hard disks (a.k.a. hard drives), optical disks and magnetic tape.

7. Media is the physical material that holds the data; capacity is how much a particular storage medium can hold; access time is the amount of time required to retrieve data and programs.

8. Floppy disks are also known as diskettes, disks, flexible disks or floppies

9. Floppy disks are made of flat circular pieces of Mylar plastic that rotate within a jacket.

10. Data is stored as electromagnetic charges on a metal oxide film coating the Mylar plastic.

11. An average Joe would use a 1.44 MB 3 ½ inch floppy disk

12. They can store 1.44 MB (about 400 typewritten pages).

13. The disks have a write-protect notch, which saves you from accidentally writing over info that you want to keep.

14. Tracks are rings on the disk that data is recorded onto. They are closed concentric rings (not a spiral) and have no visible grooves. Each track is divided into invisible wedge shaped sections called sectors.

15. Our standard disk is limited by its small capacity.

16. Floppy disks cartridges hold more information than floppy disks.

17. The examples of floppy disk cartridges (which are competing with Floppy disks) are Zip Disks, SuperDisks and HiFD disks.

18. A Zip Disk has 100 MB to 250 MB capacity (over 170 times as much as a standard floppy disk.

19. Zip drives are connected to the computer using parallel or USB ports.

20. SuperDisks (which can store 120-250 MB of info) are better than Zip disks as they are able to read and store data on the standard floppy disk drive.

21. HiFi disks are like SuperDisks in that they use the floppy disk drive. They can store around 200 MB of information.

22. Today's optical disks can hold over 17 GB of data.

23. Optical disks differ than floppy disks in that they use reflected light to represent 0's and 1's (floppy disks use electromagnetic charges to represent O's and 1's).

24. Lands are the flat areas on the disk and the bumpy areas are called pits. Light is reflected off of these, which enables the optical disk to be read.

25. The most common optical disk size is 4 ¾ inch.

26. CD stands for compact disc. They can store from 650 MB to 1 GB of info on one disc.

27. The rotational speed of the CD drive is important because it determines how fast data can be transferred from the CD. (Example: a 24X CD drive can transfer 3.6 MB of info per second however a 32X drive can transfer 4.8 MB per second) The faster the drive the faster the data can be read.

28. CD-ROM (compact disc-read only memory) cannot be written on or erased by the user. They are used to distribute large databases, reference material and software packages.

CD-R (CD-recordable) can have information written to it, however this can be done only once, and it cannot be erased. This requires a CD burner.

CD-RW (CD-rewritable) is also known as erasable optical disks. They are similar to CD-R's but the surface of the disk is not changed permanently when data is recorded.

29. DVD stands for digital versatile disc or digital video disc.

30. DVD's are similar to CDs except that they can store 4.7 - 17 GB of info.

31. DVD-ROM stands for digital versatile disc read only memory. They can provide up to 2 hours of high quality video.

DVD-R stands for DVD recordable.

DVD+ RW (DVD rewritable) and DVD RAM are 2 formats of rewritable DVD formats. DVD RW drives can also create CD discs, however DVD RAM drives cannot.