Internet : Word Wide Web

Internet : World Wide Web

The System

The World Wide Web (or simply Web) is the most popular service on the Internet. The development of the web was partly responsible for the rapid increase in the number of people who used the Internet in the late 1990s. The World Wide Web consists of millions of different sites, each of which contains information. Each site is identified by a unique address called a Uniform Resource Locator or URL.

The information at a site is stored in the form of pages which can contain text, pictures, sound and video. Because web pages can contain so many different types of information they can be designed to be attractive, informative and interesting. A page can be linked to other pages using hyperlinks. If you want to find out about a topic then you can be sure that there will be some information about the it on the web.

The Software

To look at information on the web you must use a special program called a web browser. Most web browsers will let you do these things :

View web pages on your screen and print them out.
Navigate your way from one page to another by typing in a URL, following hyperlinks or selecting a page from your favourites or history.
Keep a list of favourite web sites that you visit regularly so that you can go to them without having to remember their URLs. These favourite sites can usually be organised into categories.
Keep a list of web sites you have visited recently (your history) so that you can easily go back to them.
Store temporary copies of web pages that you have visited recently on the hard disk of your computer. If you revisit a page the browser will use the temporary copy on your computer instead of fetching the page from the Internet again. This is known as caching and speeds up access to recently viewed pages.
Send information back to a web site e.g. make a purchase from a web site by filling in a form.

When you first load your web browser it will display information from a page that you have chosen. This is known as your home page. Many users choose to have a special type of web site known as a web portal as their home page. A web portal is a page that acts as a starting point to obtain information from the world wide web. Web portals usually incorporate a search engine and hyperlinks to frequently used sites (such as news). Yahoo is an example of a web portal.

Accessing a Site

There are three methods that you can use to go to a particular page of information :

Search Engine

If you want information on a particular topic and you don’t know where to find it, you can use a search engine such as Alta-Vista to search the entire Internet for relevant pages. To use a search engine you type in a word or several words which describe the topic that you are interested in. The search engine will then list pages that it has found on the Internet which are relevant to the words that you typed in. It will usually try to put the pages into order with the most relevant near the top of the list.

Unfortunately due to the vast amount of information that is present on the Internet a search may result in tens of thousands of relevant pages being found. It is therefore very important to be as specific as possible when you use a search engine to keep the number of pages that are found to a minimum.

Hyperlinks

Each page can contain hyperlinks to other pages containing information about similar topics. If you are looking at a page on the screen then any links it contains will be highlighted (in underlined blue letters). By simply double-clicking on the link you will be taken to the page that it is a link to. Looking at web pages by clicking on links to move from one page to another is known as surfing.

Address

Each page has a unique address. If you know a page’s address (e.g. www.cedar.org) then you can type it in and go directly to the page.

Uses of the World Wide Web

Information on the world wide web can be provided by individuals or by organisations such as governments and broadcasters. Here are just a few examples of how the world wide web can be used :

Use	Details
Research	There is an incredible amount of information on the world wide web. This can be an excellent source for researching virutally any topic. The information can be up-to-date and present a variety of views. You need to be carfeul however to verify the source and accuracy of information obtained from the web.
Advertising	Many companies promote themselves by advertising on popular web sites such as search engines. These adverts often takes the form of small images called banners. Companies can also set up their own web sites to promote their products.
Distibuting Software	Traditionally software has been distributed on CD-ROM or floppy disk. Now it is possible to obtain software directly from the Internet. This is known as downloading. Usually only software that takes up relatively little storage space such as utilites and operating system updates are distributed on the web. Files that take up more space would take too long to download. Some downloaded software programs are free. Other software can be paid for online. The web is also used by software pirates to illegaly distribute copied software.
Customer Support	Companies can use the web to provide useful information to their customers. This can happen in various ways : Manuals can be provided on the web instead of in print. This means that the company can update them with the latest information. Answers to questions that customers commonly ask can be provided on the web. Customers can "chat" to company employees to get advice in a web chat room.
E-Commerce	Many companies sell their products on the web. Customers can buy them by entering their credit card details. The products are then delivered to the customers. This is known as e-commerce.

Creating a Web Site

A special computer language known as HTML is used to define the layout of pages. You can use a web design package to create your own web pages.

Advantages and Problems

This table summarises the advantages and problems of using the world wide web :

Advantages
Availability of Information	An incredible amount of information is available on the web. This is easy to access (you don't need to go anywhere) and easy to search (search engines do this automatically).
Up-to-date Information	Information on the web can be constantly updated. You can get the latest news, share prices, product support information etc.
Multimedia	Information on the web is provided as multimedia. This means that it can include text, pictures, sound and video.
Problems
Reliability of Information	Anybody can put information on the world wide web. There is no guarantee that the creator of a web site is really an expert on the topic he has written about or is who he claims to be. You need to treat information obtained from the web with care. Consider the source of the information and compare it with information from other sources.
Too Much Information	If you search for a particular topic using a search engine it will probably find tens of thousands or even millions of relevant pages. Manually looking through all these pages is very time consuming. Good pages can be missed because they are not near the top of the list of pages that were found.
Accessibility	Information on the world wide web is only available to those who can afford to and know how to use the Internet.

GCSE ICT Companion 04 - (C) P Meakin 2004