STORAGE
1.
A storage medium is the physical
material on which a computer keeps data, information, programs, and
applications.
2.
Cloud storage is another storage option,
in which the actual online storage media used is transparent to the user
3.
Capacity is the number of bytes a
storage medium can hold
4.
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
HARD
DISKS
1.
A hard
disk contains one or more inflexible, circular platters that use magnetic
particles to store data, instructions, and information
2. A
head crash occurs when a read/write
head touches the surface of a platter
3.
Always keep a backup of hard disk
4.
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
FLASH
MEMORY STORAGE
1.
Flash memory chips are a type of solid
state media and contain no moving parts
2.
SSD (solid state drive) vs HDD:
SSD
|
HDD
|
High price(1TB≈RM1000)
|
Low price(1TB≈RM160-200)
|
Smaller capacity (max1TB lp/4TB pc)
|
Big capacity (max4TB lp/10TB pc)
|
Short lifespan
|
Long lifespan
|
Low power consumption (2W)
|
Higher power consumption (7W)
|
High speed (200-550Mb/s)
|
Lower speed (50-120Mb/s)
|
3.
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
4.
USB
flash drives plug into a USB port on a computer or
mobile device.
CLOUD
STORAGE
Cloud
storage is an Internet service that provides storage to computer
or mobile device users
OPTICAL
DISCS
1.
An optical
disc consists of a flat, round, portable disc made of metal, plastic, and
lacquer that is written and read by a laser.
2.
Optical discs commonly store items in a
single track that spirals from the center of the disc to the edge of the disc
3.
Track is divided into evenly sized
sector
4.
CD
I.
A CD-ROM can be read from but not
writable or erasable.
-
Single-session disc
II.
A CD-R is an optical disc on which users
can write once, but not erase
III.
A CD-RW is an erasable multisession disc
1.
DVD
I.
A DVD-ROM is a high-capacity optical
disc on which users can read but not write on or erase
II.
A DVD-R or DVD+R are competing
DVD-recordable WORM formats, on which users can write once but not erase
III.
DVD-RW, DVD+RW, and DVD+RAM are high-capacity
rewritable DVD formats
OTHER
TYPES OF STORAGE
1.
A magnetic stripe card contains a
magnetic stripe that stores information
2.
A smart card stores data on an integrated
circuit embedded in the card
3.
Radio Frequency Identification (RFID)
4.
The RFID tag consists of an antenna and
a memory chip that contains the information to be transmitted via radio waves
5.
An RFID reader reads the radio signal
and transfers the information to a computer or computing device
6.
Microfilm and microfiche store
microscopic images of documents on a roll or sheet film
OPERATING SYSTEM
An operating system
(OS) is a set of programs containing instructions that work together to
coordinate all the activities among computer and mobile device hardware
Starting Computers and
Mobile Devices
If a computer or mobile
device is off, you press a power button to turn it on
A user interface (UI)
controls how you enter data and instructions and how information is displayed
on the screen
With a graphical user
interface (GUI), you interact with menus and visual images
How an operating system
handles programs directly affects your productivity
The operating system
determines the order in which tasks are processed
Operating systems
typically provide a means to establish Internet connections
Operating systems often
provide users with a variety of tools related to managing a computer, its
devices, or its programs
Automatic update
automatically provides new features or corrections to the program
A user account enables
a use to sign in to, or access resources on, a network or computer
A user name, or user
ID, identifies a specific user
A password is a private
combination of characters associated with the user name
Types of Operating
Systems
A desktop operating
system is a complete operating system that works on desktops, laptops, and some
tablets
Windows 8 offers these
features:
i.
Start screen interface with tiles
ii.
Includes the desktop interface
iii.
Support for input via touch, mouse, and
keyboard
iv.
Email app, calendar app, and browser
included
v.
Enhanced security through an antivirus
program, firewall, and automatic updates
vi.
Windows Store offers additional
applications for purchase
The Macintosh operating
system has earned a reputation for its ease of use
Latest version is OS X
Server Operating
Systems
Mobile Operating
Systems
The operating system on
mobile devices and many consumer electronics is called a mobile operating
system and resides on firmware
Android is an open
source, Linux-based mobile operating system designed by Google for smartphones
and tablets
iOS, developed by
Apple, is a proprietary mobile operating system specifically made for Apple’s
mobile devices
Windows Phone,
developed by Microsoft, is a proprietary mobile operating system that runs on some
smartphones
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