3. Internet: Purpose

As the previous page explains, the Internet is a computer- based communication network sharing a common protocol called TCP/IP.

But its main purpose is to allow certain services to be possible. Some of these are

• Email
• File transfer
• Real time chat
• World Wide Web
• Video and Audio streaming services
• VoIP telephone service

Each of these requires the appropriate software application and supporting hardware.

These are:

Email: Requires a dedicated email client application to send and receive emails.

Emails can also be purely a web based service. In which case a standard web browser is sufficient to send and receive emails.

File Transfer: A standard protocol called 'File Transfer Protocol' or FTP for short is used to upload and download files from an online server. A dedicated FTP application can be used. This has the advantage of being able to offer partial transfers as well, so you do not have to start from scratch if a transfer fails part way.

There are now cloud services that offer file storage and synchronisation between computers. These often have a dedicated application running on the computers to enable file transfers to take place automatically in the background. But they still use FTP as the basis of communication.

Real time chat: Also called 'Instant Messaging'. You need an IM application to operate this service. It is mainly text based but some applications allow WebCam connections as well.

Unlike email and file transfers, there is not just a single protocol in use. Many commercial providers use their own proprietary protocol which means that a person using one service cannot easily exchange chat with someone using another service. There are 'bridging' applications that try to allow talk between services.

World Wide Web: The fundamental application needed is a 'Web browser' application that can interpret the HTTP protocol being used for standard web pages. Most browser applications also allow 'Add-ins' or 'Extensions' to be installed within the browser to allow multi-media content to be viewed.

Video and Audio streaming: Music and films are streamed directly from the internet for instant viewing. Streaming means the content is not actually stored - it plays and its gone. You need a good, fast connection for the high bandwidth feeds, along with the appropriate streaming application and suitable music and television kit to view the content.

VoIP: This is a telephone service that works over the internet. Short for 'Voice over Internet Protocol'. You need a dedicated VoIP application running on the computer to make a connection.