From its humble start running on a single computer the World Wide Web better known by the letters www has become the world’s biggest source of information and entertainment Every day hundreds of millions of people turn to the Web to look at pages of images text and videos People use smartphones tablets computers to access the Internet and smart TVs as well as welcome to world the Wide web What is the Web Some people think that the Internet and the World Wide Web are the same thing They are not The Internet is the name given to the giant system of computer networks that spans the world It connects millions of computers allowing them to send digital data such as emails or files to one another The World Wide Web is a collection of information that can be accessed using the Internet The Web consists of millions of websites containing documents links and files These can be viewed by almost any device that can access the Internet 4
Web explosion Site types When the World Wide Web was established home computers were still in their early development so not many people had access to the Internet In 1993 there were just 130 websites As home computers became more popular so did the Web By 2000 there were 17 million websites Today there are over one billion websites around the world Some are simple single-page ads or personal pages created by individuals Others are built by companies or governments Some websites are vast containing thousands of different pages By 2017 the English-language edition of the encyclopedia website Wikipedia contained over 5 3 million pages COMPUTER hero British computer scientist Tim Berners Lee worked at a major science research center in Switzerland called CERN He was interested in finding new ways for scientists to share their information With the help of colleagues Berners-Lee invented the HTML coding language see page 12 for creating web pages He developed the rules known as HTTP to transmit the web pages over the Internet He also created the first web page and web server Berners-Lee launched the Internet to the world on Christmas day in 1990 Tim Berners-Lee TRUE STORY What’s in a Name The World Wide Web was nearly called the Information Mesh The Project or the Mine of Information Berners-Lee and his colleagues considered all these names before opting for World Wide Web 5
How the Web Works When you access the World Wide Web through a computer smartphone or tablet your simple request to see a web page involves a number of computers and programs all working together Web servers Keeping track Web servers are powerful computers that store all the files and data or information needed to display a website Computers or digital devices such as smartphones and tablets that communicate with the web server are known as clients A user whose computer is the client types the address of the web page they want to see Web servers keep track of which page to send to a client by using the web page’s URL Short for Uniform Resource Locator this is the address of a web page on the World Wide Web All web pages and other files on the Web such as music or video files have their own unique URL The server sends the web page over the Internet back to the client The computer displays the page on its screen The request travels over the Internet to the web server that holds that web page The server searches through its storage for the right files client request server response 6 browser web server
Understanding URLs A URL often looks like this www This tells the server that the file’s location can be found on the World Wide Web http This stands for the protocol Protocol is a series of rules and codes that help one computer talk to another http www clivelive com aboutme html clivelive com In this example this is the name of the website It is also called its domain name aboutme html This is the name of the file that is being requested In this example it is a web page but it could be an image or music file Browsing around When the web page that has been requested arrives it is displayed on the client’s computer or device by a program called a web browser or just browser Popular browsers include Mozilla Firefox Google Chrome Safari Internet Explorer and Opera They all tend to have the same main buttons and features Back and Forward These buttons allow you to leave the web page you are on and come back to it again Refresh This button reloads the web page you are on to see if it has been updated Sometimes it also helps fix a page that will not load Address bar This is where you type in URLs or topics to search for Home This button will take you back to the home page of the browser you are using 7
