the internet and world wide web: chapter 2 by silvia pereira

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

E-Mail

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