The Internet and Multimedia

Chapter 2

How the Internet Developed

• The Internet grew out of the Cold Ware between the United States and the Soviet Union following WWII

• The US and the Soviet Union competed to develop the most powerful nuclear weapons and other technologies

How the Internet Developed

• When the Soviet Union launched Sputnik, the first space satellite in 1958, the US Defense Department responded by creating the Advanced Research Projects Agency (ARPA)

• A few years later ARPA was to research how best to use the US military’s investment in computers

How the Internet Developed

• During this same time the RAND Corporation was thinking about how US government and military leaders could communicate in case of nuclear war

• In 1964 RAND proposed a computing network that was decentralized (did not depend on any one computer)…– Network – a way that computers can communicate

with each other electronically either through cables or wireless connections

How the Internet Developed

• ARPANET began operating in 1969 with a handful of computers in widely separated locations

• ARPANET went international in 1973 with computers at University College in London and the Royal Radar Establishment in Norway

• ARPANET quickly became a sort of electronic post office as well as a passageway for essential defense information

How the Internet Developed

• ARPANET spread rapidly throughout the 1970s• ARPANET could accommodate many different

kinds of computers as long as they followed the same protocol, or rules, of communication

• The original set of rules was called NCP (Network Control Protocol) but later became known as TCP/IP (Transmission Control Protocol/Internet Protocol), which was in the public domain…anyone could legally use it

How the Internet Developed

• In the late 1970s many other organizations began to link to ARPANET and the Defense department separated the military segment

• As more and more organizations acquired computers and began using TCP/IP, the interlinking of these computers and networks became known as the Internet

How the Internet Developed

• Three inventions that spread the use of the Internet were: 1. The personal computer (early 1980s)2. The World Wide Web (1989) – developed by Tim

Berners-Lee, a British software engineer• Used the concept of Hypertext which is text that is linked

to another location either on the same page or a different page

3. The browser (1991) – software application that allows you to locate and display information on the Web• Mosaic – first graphical point and click Web browser

developed in 1993 by the National Center for Supercomputing Applications (NCSA)

How the Internet Developed

• What is the difference between the Internet and the World Wide Web?– The Internet is a huge network that can connect

computers all over the world while the Web is a way a sharing information through the medium of the Internet

– The WWW always uses the Internet but the Internet doesn’t have to be connected to the WWW• Web site – a unified set of documents and related files that

are stored on a single computer and are available for display on the World Wide Web

• Web pages make up a web site

Connecting to the Internet

• In order to connect to the Internet you must have:– A modem: allows your computer to send and

receive signals though telephone or cable lines– An Internet service provider (ISP): required for all

home connections– Browser software: might need plug-in programs to

retrieve some types of media applications • Internet Explorer, FireFox, and Google Chrome

Connecting to the Internet

• A plug-in is a hardware or software application that adds a specific feature to your computer– Acrobat Reader, Flash Player, Quicktime

• Some plug-ins allow browsers to stream media which is a technique for transmitting audio and video files so they can start playing immediately without having to wait for the entire file to load first

Navigating the Web

• In order to work with multimedia on the Internet, you must understand:– The browser screen and its standard elements– URL addresses and the information they contain

Navigating the WebNavigation buttons Menu bar Web address or URL

Sidebar Main display area Hyperlinks

Standard BrowserElements

Navigating the Web

• URL – uniform resource locator; address that identifies the computer and file location of a web page so a browser can find and retrieve it

• Domain name – part of the address name of a web site that can identify the organization or type of organization hosting the site

Navigating the Web

• Domain Name ExtensionsExtension Type of Organization

.com Commercial Business

.gov Government

.edu Educational institution

.mil Military

.info Information

.org Nonprofit

.net Network

.biz Commercial Business

.pro Professional (such as a law firm)

Searching the Web

• If you already know the URL, type it in the browser’s Web address area

• If you have visited the site before the URL is probably saved and will appear as you are typing it

Searching the Web

• If you don’t know the URL, use a search engine which is a web site with database software that locates documents on the Web by searching for specific words– Create search queries that include keywords• Search query – a list of keywords and other information

that a search engine uses to locate Web pages• Keyword – a word that is likely to appear in the

document you want to find

Searching the Web

• Most search engines work the same way but some are more powerful than others…depending on their indexes or easier to create queries

• Most search engines results are ranked with the pages most likely to contain the information you want

• Most companies develop and maintain their search engines by posting advertisements on their sites

Searching the Web

• If your query is to general you may find millions of pages or hits and may have little or no relation to the information you want– The more precise you are, the more likely it is to

get a short list of pages containing helpful information

Searching the Web

• Boolean searches use formulas with operators (and, or, not, near) that tell the search engine how to use your keywords– Symbols (quotation marks, parentheses, and

asterisk) can also be used in your search

Communicating Via the Internet• There are several ways to communicate on the Internet:

– E-mail: Sent to a specific e-mail address. Can have attachments (text, pictures, and/or videos)

– File transfer protocol (FTP): Often used to transfer large files from one computer to another.

– Chat rooms: “Virtual” rooms where you can exchange typed messages with others who are in the room.

– Instant messaging: Allows you to communicate in real time with one person.

– Social networking: basically it's a profile page of yourself and about you, and then you connect to the profile sites of others

– Blogs: short for web log; basically an online dairy; may also be called a journal