Internet

Standard Grade Computing

Internet

• a wide area network spanning the globe.

• consists of many smaller networks linked together.

Service

• a way of using the internet to perform specific tasks

Services available on the Internet

Three main services:

World Wide Webgives access to information in remote computers through browsing or searching

Emailmessages between computers

File transferto send or receive large files

Other services

Chata web site where users can take part in text discussions with other users

Instant messaginga program that looks for your friends online and tells you that they can receive messages

Bulletin boards (forums)an electronic notice board where users can post, read, look at messages

Discussion groupgeographically separated users with a common interest hosted on a web site

Web logs a web page made up of short entries in chronological (time) order like a diary

On-line banking

On-line shopping

Video streamingthe process of receiving video images over a network and displaying them on a computer screen

Video Conferencinguses communication links to conduct meetings between people who are geographically separated. Requires a computer system and a webcam in each location together with a network connection

To connect to the Internet you need:

computer system

modem

communications software eg. browser and email client program

Internet Service Provider (ISP)

Internet Service Provider (ISP)

A company that provides a host computer connected to the Internet which the user can access. The host computer manages communications and stores data such as email and web pages

Modem

a piece of hardware that changes the digital signals from a computer into “telephone signals” which can be sent along a normal telephone line. A modem at the other end changes the signals back into digital form for the receiving computer.

Internet ready computer – consists of:

• computer system

• internal modem

• communications software eg. browser and email client program

Mobile Internet Technologies

Includes palmtops, laptops, mobile phones.

Do not need a mains power supply or physical connection to the Internet, which can be achieved using wireless networking interface cards.

Dial-up connection

a wire connects the computer’s modem socket to the telephone socket. The communication software dials the ISP’s number and establishes a connection to the Internet.

Broadband connection

constantly connected to the Internet, much faster access. Telephone can be used at same time. More than one computer can be connected to Internet at same time.

Another definition of online…

Online – connected to the Internet.

Offline – disconnected.

Downloading Software

Downloading

Receiving a file from a network (server or individual computer) and saving it onto a computer system.

Freeware

Totally free software that can be used on any number of computer systems.

Downloading Software

Shareware

Free for a short trial period to let you try it. After that you must either delete the software or pay to continue using it. Some crucial functions usually missing (e.g. save, print).

Commercial software

Must be paid for. Can only be used on one computer without a special license. You cannot legally make copies.

World Wide Web

Browser

• a program that allows the user to access web pages (surf the net) eg. Internet Explorer

Web page

• a single document or file on the World Wide Web

• identified by a unique URL (Universal Resource Locator)

• can used to hold information in multimedia form

World Wide Web

Hyperlink

Links Web pages, documents or files; activated by clicking with the mouse.

HTML

Hypertext mark-up language. A special language used to create Web pages.

Search Engine

A site designed to help you find information. The user can enter keywords.

Simple Search

The user enters one or more keywords

Complex Search

Allows the user to refine a search by restricting the search to only parts of the Web. Most allow the use of AND ( +), OR, NOT ( - ) eg. mountain + scotland

The Big Bad World Wide Web

Is inhabited by?

Who controls it?

Who checks the information is correct?

Who has access•to the WWW?•to your data on the WWW?

Creating a web page

Simplest way is to use• a wizard or• a template

You can then • enter your text• add graphics

Creating a better web page

To create a more interesting page, add

• audio• video• hyperlinks using text or hotspots (A

defined area in a graphic containing a hyperlink)

Present information using tables

Internet

Standard Grade ComputingEnd of presentation