THE INTERNET AND WORLD WIDE WEB:
Chapter 2
by Silvia Pereira
History of the Internet
Began as a networking project by the Pentagon– Goal was to build a network that:
Allowed scientists from around the world to share information and work together
Could work even if part of the network was destroyed by a disaster
How the Internet Works
Connecting to the Internet– Dial-up access
The modem on the computer uses a telephone line to connect (slow speed)
– DSL and ISDN A higher speed connection using regular copper telephone
wires
– Cable Modem Provides high-speed connection through a cable television
network
Access Providers
These are businesses that give people and companies access to the Internet for a fee.– An ISP gives phone numbers which allow access
Connects people to an access point (point of presence: POP)
– An OSP includes member-only features– A WSP provides wireless access to users with
wireless modems or Web-enabled mobile devices
How Data Travels the Internet
Connected computers work together to transfer data and information around the world – Use servers and clients
Carriers of network traffic are known as the Internet backbone
Data is transferred from one network to another until it reaches its final destination
Internet Addresses
An addressing system is needed to send data to a specific destination– An IP address is a number that uniquely identifies
each computer to the Internet– A Domain name is the text version of an IP address
Every domain name has a top-level domain, identifying the organization associated with the domain
The World Wide Web
Each document on the Web is called a Web page
A Web site is a collection of related pages and items that are stored on a Web server
A Web browser allows users to use pages A home page is the first page a Web site
shows– Can be changed to whatever the user wants it to be
Downloading is how a computer gets information
Web Addresses
Each Web page has a unique address, known as a URL
A URL is typed into the Address text box at the top of the browser window– It consists of a protocol, domain name, and maybe a
path to a specific page
A Web server is a computer that sends requested pages to computers
Navigating Web Pages
Links– Connect from a Web page to another related page
Nonlinear way to get information
– Use of links is referred to as “surfing the Web”– Are usually underlined and in a color different from
the other text on that page
Searching for Info on the Web
A search engine finds Web sites and pages about chosen topics– Keywords are entered in the text box– Hits, or Web page names that contain text with the
keywords, are displayed
A spider is a program that saves the list of keywords used
A subject directory puts pages into a set of categories
Types of Web Pages
Portal News Informational Business/Marketing
Educational Entertainment Advocacy Personal
Caution! No one oversees the contents of these pages, so don’t assume they’re accurate.
Multimedia on the Web
An application that combines text with:– Graphics– Animation– Audio– Video– Virtual reality– Plug-Ins
E-Commerce
A business transaction occurring over the Web– B2C: sale of goods and services to the public
Electronic storefront
– C2C: when one consumer sells directly to another Online auction
– B2B: when a business offers goods and services to another business
Technical support
It’s the transmission of messages and files via a computer network– E-mail program: used to conduct e-mails– One must address to whom e-mail is being sent to
An address has a user name and a domain name A user name is unique to each user in a domain
– Address books are useful Contains a list of names and e-mail addresses
FTP and Mailing Lists
File Transfer Protocol– Permits file uploading and downloading
Mailing Lists– Group of e-mail names and addresses under a
single name Everyone on that list receives a copy of a message in their
mailbox Can subscribe and unsubscribe
Newsgroups and Message Boards
Newsgroups:– Online area where users have discussions about a
particular subject through articles– Members send messages so others can reply
Thread: a discussion that’s made up of an original article and all subsequent replies
– A news server stores and distributes messages– Message boards are similar to newsgroups, but they
don’t need a newsreader to participate in discussion
Chat Rooms and Instant Messaging
Chat rooms– Place on the server that allows users to chat
Chat: a real-time conversation– Real-time: people are conversing online at the same time; no
time elapse
Instant Messaging– Communication service that allows people to
exchange message or files Also in real-time
Netiquette
Code of acceptable behaviors users should follow on the Internet– Avoid offensive language– Avoid sending spam– Don’t use all capital letters
It’s like SHOUTING!
– Use emoticons to express emotion : )
– Use abbreviations and acronyms for phrases BRB means Be Right Back
Web Publishing
It’s the development and maintenance of Web pages
Five major steps to Web publishing– Plan a Web site– Analyze and design a Web site– Create a Web site– Deploy a Web site– Maintain a Web site
5 Steps of Web Publishing
Plan a Web site– Identify the purpose of the site– Determine ways to make the site unique
Analyze and design a Web site– Determine how to meet the aforementioned goals– Design the layout
Text, graphics, audio, video, and virtual reality
– Decide if this is possible, or if it is taking on too much
5 Steps of Web Publishing cont’d
Create a Web site– Compose the site
Deploy a Web site– Store the site on a Web server
Registering the site with search engines is a good way to ensure many people see it, for it will appear in the hit list for searches on related keywords
Maintain a Web site– Frequently make sure information is updated and
links are current