Introduction to Information Technology: Your Digital World
Using Information Technology, 10e
5
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
2
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
3
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Internet history
•
•
•
•
•
•
Began with 1969s ARPANET for U.S. Dept. of Defense
62 computers in 1974
500 computers in 1983
28,000 computers in 1987
Early 1990s, multimedia became available on Internet
2010 = about 2 billion people on Internet
• To connect you need
• 1. An access device (computer with modem)
• 2. A means of connection (phone line, cable hookup, or
wireless)
• 3. An Internet access provider
4
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
DEFINITION: Bandwidth is an expression of how
much data – text, voice, video, and so on – can be
sent through a communication channel in a given
amount of time.
DEFINITION: Baseband is a slow type of connection
that allows only one signal to be transmitted
at a time.
DEFINITION: Broadband is a high-speed connection
that allows several signals to be transmitted at
once.
5
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Data Transmission Speeds
• Originally measured in bits per second (bps)
• 8 bits are needed to send one character, such as
A or a
• Kbps connections send 1 thousand bits per second
• Mbps connections send 1 million bits per second
• Gbps connections send 1 billion bits per second
• Uploading & Downloading
• Upload—transmit data from local to remote computer
• Download—transmit data from remote to local computer
6
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• DSL line
• Uses regular phone lines, DSL modem
• Receives data at 1.5 ̶ 10 Mbps; sends at 128 Kbps –
1.5 Mbps
• T1 line—very expensive
• Traditional trunk line; carries 24 normal telephone
circuits
• Transmission rate of 1.5 ̶ 6 Mbps (T3 = 6 – 45 Mbps)
• Cable modem
• Receives data at up to 30 Mbps; sends at about 1.4
Mbps
Using Information Technology, 10e
7
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Transmits data between satellite dish
and satellite orbiting earth
• Sends data at around 200 ̶ 512 Kbps;
receives at 1 ̶ 5 Mbps
• Connection is always on
• User needs to buy or lease satellite dish and
modem and have them connected
8
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Wi-Fi & 3G/4G
• Wi-Fi—stands for “wireless fidelity”
• Transmits data wirelessly up to 54 Mbps for 300 – 500 feet
from access point (hotspot)
• Typically used with laptops and tablets that have Wi-Fi
hardware
• 3G—stands for “third generation”; 4G = “fourth
generation”
• High-speed wireless that does not need access points,
because it uses existing cellphone system
• Used mostly in smartphones
9
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Two Types
• 1. Internet Service Provider (ISP) — e.g., Earthlink
and Comcast
• Company that links online users to its servers, which link
users to the Internet through another company’s network
• 2. Wireless Internet Service Provider (WISP) — e.g.,
AT&T, Cingular, Verizon
• Enables wireless-equipped laptop/tablet and smartphone
users to access Internet
10
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
11
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• The Internet consists of hundreds of thousands
of smaller networks
• Protocols
• The set of rules a computer follows to electronically transmit data.
• TCP/IP (Transmission Control Protocol/Internet Protocol) is the
Internet protocol
• Developed in 1978 by ARPA; used for all Internet transactions
• Packets
• Fixed-length blocks of data for transmission
• Data transmissions are broken up into packets and re-assembled
at destination (the IP—Internet Protocol— address)
12
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Every device connected to the Internet
has an address
• Each IP address uniquely identifies that
device
• The address is four sets of numbers
separated by periods (e.g., 1.160.10.240)
• Each number is between 0 and 255
13
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
14
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• The web and the Internet are not the same; the web is
•
multimedia-based, and the Internet is not. The Internet
is the infrastructure that supports the web.
Browsers
• Software for web surfing (for accessing particular servers
on the Internet); examples = Internet Explorer
Mozilla FireFox
Apple Macintosh’s Safari
Google’s Chrome
15
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Website
• The location on a particular computer (server) that has a
unique address; example = www.philadelphia.edu.jo
• The website (server) could be anywhere — not necessarily at
company headquarters
• Web Page
• A document on the web that can include text, pictures, sound,
and video
• The first page on a website is the Home page
• The Home page contains links to other pages on the website
(and often other websites)
16
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• TCP/IP— As explained, general Internet Protocol
• HTTP—Protocol Used to Access World Wide
•
Web
Hypertext Markup Language (HTML)
• The “markup” language used in writing
and publishing web pages
• Set of instructions used to specify
document structure, formatting,
and links to other documents on the web
• Hypertext links connect one web document to
another
17
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Web browsers interpret HTML and allow you to
•
move around the Internet and the web
Come preinstalled on most PCs, but you can
download others
18
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Organizations that maintain databases
accessible through websites to help you find
information on the internet
• Examples: portals like Yahoo! and Bing, plus Google,
Ask.com, Gigablast
• Search services maintain search engines—programs
that users can use to ask questions or use keywords
to find information
19
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Tagging
• Tags: do-it-yourself labels that people can put on
anything found on the internet, from articles to
photos to videos
• Can be shared easily with other people
• Tags are available through
delicious.com, BlinkList, Flickr
20
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
21
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Uses the Internet to make phone calls via VoIP
•
•
•
(Voice over Internet Protocol)
Long-distance calls are either very inexpensive
or free
With a PC that has a sound card, microphone,
Internet connection with modem & ISP, and
internet telephone software such as Skype and
Vonage
Also allows videoconferencing
22
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• E-Commerce (electronic commerce):
conducting business activities online
• B2B commerce is business-to-business e-commerce
• Online finance involves online banking, stock trading
online, and e-money such as PayPal
• Online auctions link buyers with sellers (e.g., eBay)
• Online job hunting match job hunters with employers
Discussion Question: Have you every sold anything on eBay?
Used PayPal? Did you have any problems? What would you
warn people about?
23
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
 The move toward a more social, collaborative,
interactive, and responsive web; has led to the “social
web,” giving rise to:
 Social networking sites: Facebook, MySpace
 Social networking website: an online community that
allows members to:
 Keep track of friends
 Share photos, videos, music, stories, and ideas
 Media-sharing sites: YouTube, Flicker, Shutterfly, etc.
 Media-sharing website: type of online social network in
which members share media such as photos, videos,
music, ideas, and so forth
24
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
25
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
Malware refers to software programs designed
to damage or do other unwanted actions on a
computer system.
• Spamming
• Cookies
26
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
 Spam: Electronic Junk Mail




Unsolicited email that takes up your time
Delete it without opening the message
Never reply to a spam message
When you sign up for something, don’t give your
email address
 Use spam filters
 Fight back by reporting new spammers to
www.abuse.net or www.spamhaus.org
27
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.
Introduction to Information Technology: Your Digital World
• Cookies
• Little text files left on your hard disk
by some websites you visit
• Can include your log-in name,
password, and browser preferences
• Can make visiting these websites next
time more convenient and faster
• But cookies can be used to gather
information about you and your
browsing habits; this information can
be used without your consent
28
Using Information Technology, 10e
© 2013 The McGraw-Hill Companies, Inc. All rights reserved.