Business information systems

Based on Chapter 8 in the textbook. 

An old aphorism claims, “You can never have too much money.” Many computer users support a similar maxim, “You can never have too much storage.” Although some computer users turn to hardware solutions for the problem of adequate storage, other users look to software answers, such as hard disk partitions or data compression. Information about both partition software and data compression software is available on the web. 

Visit some websites to find out more about hard disk partitions and data compression. 

Questions

1. How do partitions increase the capacity of hard disks? 

2. What kind of data compression is most suitable for communications devices? 

3. What are the most well known data compression algorithms? 

4. How can compression ratios of different algorithms be compared? 

5. What are some formats for data compression archives?

Expectations

• Do provide at least one supporting reference. 
• There should be minimum of three sentences for each of the questions for a total of five paragraphs. Should average out to 2.5 pages in APA format. 

Chapter 8
Digital Storage
Discovering Computers
Technology in a World of Computers,
Mobile Devices, and the Internet

1

Objectives Overview
Discovering Computers 2014: Chapter 8
2
See Page 336
for Detailed Objectives

2

Differentiate between storage and memory

Describe the characteristics of internal hard disks

Identify uses of external hard disks and RAID

Describe the benefits of solid-state drives

Differentiate among various types of memory cards and USB flash drives

Objectives Overview
Discovering Computers 2014: Chapter 8
3
See Page 336
for Detailed Objectives

3

Discuss the benefits and uses of cloud storage

Describe characteristics of and differentiate among types of optical discs

Explain types of enterprise storage

Identify uses of magnetic stripe cards, smart cards, RFID tags, and microfilm and microfiche

Storage
Discovering Computers 2014: Chapter 8
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Page 336

4

A storage medium is the physical material on which a computer keeps data, information, programs, and applications

Cloud storage is another storage option, in which the actual online storage media used is transparent to the user

Storage
A storage device is the hardware that records and/or retrieves items to and from storage media
Discovering Computers 2014: Chapter 8
5
Page 336

5

Reading is the process of transferring items from a storage medium into memory

Writing is the process of transferring items from memory to a storage medium

Storage
Discovering Computers 2014: Chapter 8
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Page 337
Figure 8-1

6

Storage
Capacity is the number of bytes a storage medium can hold
Discovering Computers 2014: Chapter 8
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Pages 336 and 338
Table 8-1

7

Storage
Items on a storage medium remain intact even when you turn off a computer or mobile device
Discovering Computers 2014: Chapter 8
8
Page 338
Figure 8-2

Storage
Access time measures:
The amount of time it takes a storage device to locate an item on a storage medium
The time required to deliver an item from memory to the processor
Discovering Computers 2014: Chapter 8
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Page 339
Figure 8-3

9

Hard Disks
A hard disk contains one or more inflexible, circular platters that use magnetic particles to store data, instructions, and information
Discovering Computers 2014: Chapter 8
10
Pages 339 – 340
Figure 8-4

10

Hard Disks
Hard disks can store data using longitudinal recording or perpendicular recording
Discovering Computers 2014: Chapter 8
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Page 341
Figure 8-5

11

Hard Disks
Formatting is the process of dividing the disk into tracks and sectors
Discovering Computers 2014: Chapter 8
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Page 342
Figure 8-6

12

Hard Disks
Characteristics of a hard disk include:
Discovering Computers 2014: Chapter 8
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Page 342

13

Tracks

Sectors

Platters

Form factor

Read/write head

Revolutions per minute

Hard Disks
Discovering Computers 2014: Chapter 8
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Page 342
Figure 8-7

14

Hard Disks
A head crash occurs when a read/write head touches the surface of a platter
Always keep a backup of your hard disk
Discovering Computers 2014: Chapter 8
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Page 343
Figure 8-8

15

Hard Disks
Discovering Computers 2014: Chapter 8
16
Page 343
Disk cache, sometimes called a buffer, consists of a memory chip(s) on a hard disk that stores frequently accessed data, instructions, and information
The larger the disk cache, the faster the hard disk

16

Hard Disks
RAID (redundant array of independent disks) is a group of two or more integrated hard disks
Discovering Computers 2014: Chapter 8
17
Page 343
Figure 8-9

17

Hard Disks
Discovering Computers 2014: Chapter 8
18
Pages 343 – 344
Figure 8-10
An external hard disk is a separate freestanding storage device that connects with a cable to a USB port or other port on a computer or mobile device

18

Flash Memory Storage
Flash memory chips are a type of solid state media and contain no moving parts
An SSD (solid state drive) has several advantages over magnetic hard disks:
Discovering Computers 2014: Chapter 8
19
Pages 345 – 346

19

Higher storage capacities

Faster access times

Faster transfer rates

Quieter operation

More durable

Lighter weight

Less power consumption

Less heat generation

Longer life

Flash Memory Storage
Discovering Computers 2014: Chapter 8
20
Page 346
Figure 8-11

20

Flash Memory Storage
A memory card is a removable flash memory device that you insert and remove from a slot in a computer, mobile device, or card reader/writer
Discovering Computers 2014: Chapter 8
21
Pages 347 – 348

21

CF

SDHC

SDXC

miniSD

microSD

microSDHC

microSDXC

xD Picture Card

Memory Stick PRO Duo

M2

Flash Memory Storage
Discovering Computers 2014: Chapter 8
22
Page 347
Figure 8-12

22

Flash Memory Storage
Discovering Computers 2014: Chapter 8
23
Page 348
Figure 8-13

23

Flash Memory Storage
USB flash drives plug into a USB port on a computer or mobile device
Discovering Computers 2014: Chapter 8
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Page 350
Figure 8-14

24

Cloud Storage
Cloud storage is an Internet service that provides storage to computer or mobile device users
Discovering Computers 2014: Chapter 8
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Page 351

25

Optical Discs
An optical disc consists of a flat, round, portable disc made of metal, plastic, and lacquer that is written and read by a laser
Discovering Computers 2014: Chapter 8
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Page 353
Figure 8-15

26

Optical Discs
Discovering Computers 2014: Chapter 8
27
Page 353
Figure 8-16

27

Optical Discs
Optical discs commonly store items in a single track that spirals from the center of the disc to the edge of the disc
Track is divided into evenly sized sectors
Discovering Computers 2014: Chapter 8
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Page 354
Figure 8-17

28

Optical Discs
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Page 355

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A CD-ROM can be read from but not written to

Single-session disc

A CD-R is an optical disc on which users can write once, but not erase

A CD-RW is an erasable multisession disc

Optical Discs
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Page 355

30

A DVD-ROM is a high-capacity optical disc on which users can read but not write on or erase

A DVD-R or DVD+R are competing DVD-recordable WORM formats, on which users can write once but not erase

DVD-RW, DVD+RW, and DVD+RAM are high-capacity rewritable DVD formats

Enterprise Storage
Enterprise hardware allows large organizations to manage and store data and information using devices intended for heavy use, maximum efficiency, and maximum availability
RAID duplicates data, instructions, and information to improve data reliability
Discovering Computers 2014: Chapter 8
31
Pages 358 – 359
Figure 8-19

Enterprise Storage
Network attached storage (NAS) is a server that is placed on a network with the sole purpose of providing storage to users, computers, and devices attached to the network
Discovering Computers 2014: Chapter 8
32
Page 359
Figure 8-20

Enterprise Storage
A storage area network (SAN) is a high-speed network with the sole purpose of providing storage to other attached servers
Discovering Computers 2014: Chapter 8
33
Pages 359 – 360
Figure 8-21

Enterprise Storage
Tape is a magnetically coated ribbon of plastic capable of storing large amounts of data and information
A tape drive reads and writes data and information on a tape
Discovering Computers 2014: Chapter 8
34
Page 360
Figure 8-22

34

Other Types of Storage
A magnetic stripe card contains a magnetic stripe that stores information
A smart card stores data on an integrated circuit embedded in the card
Discovering Computers 2014: Chapter 8
35
Pages 361 – 362
Figure 8-24

35

Other Types of Storage
The RFID tag consists of an antenna and a memory chip that contains the information to be transmitted via radio waves
An RFID reader reads the radio signal and transfers the information to a computer or computing device
Discovering Computers 2014: Chapter 8
36
Page 363
Figure 8-25

Other Types of Storage
Microfilm and microfiche store microscopic images of documents on a roll or sheet film
Discovering Computers 2014: Chapter 8
37
Page 363
Figure 8-26

37

Summary
Discovering Computers 2014: Chapter 8
38
Page 365

38

Variety of storage options

Storage capacity and storage access times

Characteristics of hard disks, RAID, and external hard drives

Various types of flash memory storage

Advantages and various uses of cloud storage

Characteristics of optical discs

Enterprise storage options

Chapter 8 Complete

Chapter 8
Digital Storage
Discovering Computers
Technology in a World of Computers,
Mobile Devices, and the Internet

39