ICT - Web applications

Global communications system linking computers geographcally through use of telecommunications.

Allows for faster communication between computers and transfer of data.

Any computer can be linked to any other through the internet by having: common technical standards, common identification system, common reference system for data files.

WWW is a collection of information on a computer connected to the internet.

Held in multimedia form and stored in locations called websites.

Process of searching web for information is called surfing

a URL is a unique web adress for referring to resources on the internet.

http://CCEA.org.uk/DigitalTechnology.html

http:// = protocol - accesing the resources

CCEA.org.uk = domain name - name of site

/DigitalTechnology - Filename of any extension required

Protocol that defines the process of identifying, requesting and transferring multimedia web pages over internet. These web pages are usually constructed using HTML and a secure variant HTTPS exists.

Each computer linked to internet has a physical adress called an IP address. It uniquely identifies the computer.

IP addresses are in the form: 158.152.1.58

Computers connected to internet at all times have a static IP address that doesnt change or else a dynamic IP adress that changes on logging in.

Application running on a users computer that is responsible for requesting the text and graphics of webpages from servers on the internet, and assembling them for display.

E.g. Internet explorer, Apple safari, Google Chrome

Provides internet pages for other computers through the internet. It often provides the cache of web pages, which are pages stored when first accessed so they can be supplied later without having much delay.

Type of internet hosting servive that allows individuals and organistations to make website available to WWW. Web hosts are companies that provide space on a server owned or leased for the use of clients. Can also provide data center space and connectivity to the internet for other servers located in their data center.

FTP is commonest protocol for movement of files across internet. Users access a server holding the required file and request that it be downloaded to them or a user can send a file to a server that will accept uploads.

When a user downloads files through FTP they are given freer access to the file server than to a web server.

An organisation that has direct links to the internet and accepts transmission from users over dialup or broadband connections, and passes these onto the internet. Most individual users of the internet access through any one of a number of commercial internet service providers e.g. BT, Sky