2. Distinguish between primary and secondary storage.
Discuss the important characteristics of secondary storage, including media, capacity, storage devices, and access speed.
Describe hard disk platters, tracks, sectors, and head crashes.
Compare internal and external hard drives.
Discuss performance enhancements including disk caching, RAID, file compression, and file decompression.

3. Define optical storage including compact, digital versatile, and high-definition discs.
Define solid-state storage, including solid-state drives, flash memory, and USB drives.
Define cloud storage and cloud storage services.
Discuss mass storage devices, enterprise storage systems, and storage area networks.

4. Data storage has expanded from text and numeric files to include digital music files, photographic files, video files, and much more.
These new types of files require secondary storage devices with much greater capacity.
In this chapter, you learn about the many types of secondary storage devices including their capabilities and limitations.

5. Secondary storage characteristics
Primary storage
Volatile storage
Temporary storage
Random Access Memory (RAM)
Secondary storage
Nonvolatile storage
Permanent storage
Secondary storage characteristics
Media
Capacity
Storage devices
Access speed
Secondary storage permanently saves information for future use; to share information with others; to modify at later date
Secondary storage is nonvolatile – stores programs and data as opposed to temporary storage (RAM)
Characteristics include:
Media or medium – actual physical materials that holds the data and programs
Capacity – measures how much a particular storage medium can hold
Storage devices – hardware that reads data and programs from storage media (most also write to storage media)
Access speed or access time – measures the amount of time required by the storage device to retrieve data and programs
Writing– process of saving information to the secondary storage device
Reading – process of accessing information from secondary storage

6. Provides permanent or nonvolatile storage
Data and programs can be retained after the computer has been shut off
Most desktop microcomputer systems have both hard and optical disk drives
Optical disks – large storage capacity (Key Term)
Hard disk – large storage capacity and fast retrieval times

7. Store and organize files using tracks, sectors, and cylinders
Use rigid, metallic platters that are stacked one on top of one another
Store and organize files using tracks, sectors, and cylinders
Large capacity (terabytes)
Susceptible to head crash
Two types of hard disks:
Internal Hard Disk
External Hard Disks
Performance enhancements
Composed of metallic rather than plastic disks
Platters – rigid metallic, stacked one on top of another
Track-rings of concentric circles
Each track is divided into wedge-shaped sections called sectors
A cylinder (Key Term) runs through each track of a stack of platters
Fast information storage and retrieval

8. Occurs when read-write head makes contact with the hard disk’s surface or with particles on its surface
Disastrous
Read-write head is inch above surface
Return

9. Located inside system unit and often designated as the C: drive
Used to store programs and data files
Advantages over removable media
Capacity
Access speed
Located inside the system unit
Used for storing the operating system, other programs, and large data files
You should perform routine maintenance and periodically backup all important files
Return

10. Removable hard disks
Used to complement internal hard disk with an unlimited amount of additional storage
Connect to a USB or FireWire port
Used to complement internal hard disk.
Return

11. Disk caching to improve hard disk performance
Redundant arrays of inexpensive disks (RAID) to expand storage and to improve access speed
File compression and decompression to increase capacity
Disk caching
Uses hardware and software to anticipate data needs; performs function similar to RAM caching; improves processing by acting as a temporary high-speed holding area between a secondary storage device (Key Term) and the CPU
Frequently used data is stored in memory; when needed, the access time is much faster
Redundant arrays of inexpensive disks (RAID)
Groups of low cost hard-disk drives grouped together using networks and special software
Performs as a single large-capacity disk; but faster than a single disk of comparable size
Often used by Internet servers and large organizations
File compression and decompression
Increase storage capacity
Reduce space required for storage; reduce up to ¼ of original size
WinZip is a well-known program, and you can also use utility programs in Windows.
Return

12. Hold over 100 gigabytes (GB) of data Attributes
Lands
Pits
Three types
Compact Disc (CD)
Digital Versatile Disc (DVD)
Blu-Ray (Hi-Def) Disc
Use laser technology. CD (Key Term) and DVD (Key Term) are optical disk formats.
Compact, high capacity form of permanent storage (up to 50 gigabytes of data)
Optical discs are read by an optical disc drive
Laser beam writes by creating a pattern of pits (holes) and lands (flat areas) to encode data bits
Laser beams reflect off the pits and lands to read the data
Rotational speed determines how fast data can be transferred from the CD
Optical disks come in many different sizes
Most common is 4 ¾ inches
Stored in a protective case called jewel boxes

13. Optical format Capacity of 650 MB to 1 GB Rotation speeds vary
Three basic types
Read only (CD-ROM)
Write once (CD-R)
Rewriteable (CD-RW)
CD stands for compact disc
Standard on most computers; can store from 650 MB up to 1 GB
Speed determines how fast data can be transferred
Read only: CD-ROM
Commercial music CD
Read only means it cannot be written on or erased
Used to distribute large databases and references
Write once: CD-R (CD-recordable)
Used to archive data or to record music downloaded from the Internet
Rewriteable: CD-RW
Known as erasable optical disks (Key Term)
Can be changed
Used to create and edit multimedia presentations
Ideal for use as permanent data archives for essential company information
Return

14. Like CDs, but newer format called digital versatile disc or digital video disc (DVD)
Capacity of 4.7 GB to 17 GB
Three basic types
Read only (DVD-ROM)
Write once (DVD+R and DVD-R)
Rewriteable (DVD+RW, DVD-RW, and DVD-RAM)
Return

15. Next generation optical disc for recording high-definition (hi def) video
Capacity of 25 GB to 128 GB
Blu-ray optical drives are usually capable of reading standard DVDs and CDs in addition to Blu-ray discs
Blu-ray, also known as BDs
Have a capacity of 25 to 128 gigabytes
Blu-ray has seemingly won the battle as the standard high definition video disc
Like CDs and DVDs, Blu-ray has three basic types: read only, write once, and rewritable.
Return

16. Solid–state drives (SSDs)
No moving parts
Faster and more durable than hard disks
Flash memory cards
Widely used in computers, cameras, and portable devices such as mobile phones and GPS navigation systems
USB Drives (or Flash Drives)
Connect to USB port
Capacity of 1 GB to 256 GB
Solid state drives are faster and more durable (no moving parts) than hard drives
Require less power
Contain solid state memory instead of magnetic disk to store data
Used for tablet PCs, like the iPad
Flash memory cards are one type of solid state device.
Used in digital cameras, ipods

17. Cloud computing is where the Internet acts as a “cloud” of servers
Applications provided as a service rather than a product
Supplied by servers
Google Apps
Mint.com
The processing power of the service provider’s server is used to run the applications and your computer is responsible only for displaying the results.
The applications and data can be accessed from any Internet-ready device. This means that devices with little storage, memory, or processing power, such as mobile phones, can run the same powerful applications as a desktop computer.
Cloud servers provide storage, processing, and memory.
Software installation and upgrades are avoided.

19. Using a cloud storage service makes it easy to upload and share files with anyone.

20. Large amounts of secondary storage called mass storage
An enterprise storage system strategy ensures efficient and safe use of data across an organizational network Devices include:
File servers
Networked attached storage (NAS)
RAID systems
Tape libraries
Organizational cloud storage
Mass storage devices that support enterprise storage systems are
File servers (Key Term) – dedicated computer with very large storage capacities that provide user access to fast storage and retrieval of data
Network attached storage (NAS) – similar to a files server except less expensive
RAID systems (Key Term) – larger versions of the specialized devices discussed earlier in this chapter that enhance organizational security by constantly making backup copies of files moving across the organization’s networks
Tape library (Key Term) – device that provides automatic access to data archived on a large collection or library of tapes
Organizational cloud storage – high speed internet connection to a dedicated remote organizational cloud storage server.

22. Architecture to link remote computer storage devices, such as enterprise storage systems, to computers such that the devices are available as locally attached drives
User’s computer provides file system, but SAN provides disk space
House data in remote locations and still allow efficient and secure access

23. General employer requirements
Software engineers analyze users’ needs and create application software
General employer requirements
Bachelors degree in computer science
Extensive knowledge of computers and technology
Communication and analytical skills
Annual salary of $63,000 to $98,500

24. Future secondary storage disks will eventually store terabytes (TB) or petabytes (PB)
Your entire life captured in digital video on a single disc
Currently developing programs that can scan photos and videos for a particular person’s face
Are there downsides?
Could your personal video log be used to incriminate you in a court of law?
Could someone else’s video log be an invasion of your right to privacy?

25. Compare primary storage and secondary storage and discuss the most important characteristics of secondary storage.
Discus hard disks including density, platters, tracks, sectors, cylinders, head crashes, internal, external, and performance enhancements.
Discuss optical disks including pits, lands, CDs, DVDs, Blu-ray, and hi def.
Have students turn to the end of Chapter 8 in their textbooks to view the same “Open-Ended” questions/statements

26. Discuss cloud computing and cloud storage.
Discuss solid-state storage including solid-state drives, flash memory, and USB drives.
Discuss cloud computing and cloud storage.
Describe mass storage devices including enterprise storages systems, file servers, network attached storage, RAID systems, tape libraries, organizational cloud storage, and storage area network systems.
Have students turn to the end of Chapter 8 in their textbooks to view the same “Open-Ended” questions/statements