DT Web Applications

• Provides internet pages for other computers through the internet
• Often provides cache of webpages
• Webpages are stored when first accessed so they can later be accessed without internet access

Provides/delivers web pages/resourses.[1] In response to requests from web users.[1] 

• Type of internet hosting service, allows individuals and organisations to make the website accessiable via the world wide web.
• Web hosts are companies that provide space on a server owned or leased for use by clients.

A web hosting service is a type of internet hosting service that allows individuals and organisations to make their website accessible via the world wide web.[1] Web hosts are companies that provide space on a web server owned or leased for use.[1]

• Commonest protocol (set of rules) for file movement across the internet
• Users can access a server holding the required file and request that it is downloaded to them.
• Or a user can send the file to a server which will accept uploads, in this way personal web pages are delivered to the web server where they are stored
• When a file is downloaded through FTP they are given freer access to the file server
• They can normally see the listing of all files and folders, may be able to navigate through the directory structure
• Passwords and usernames are required to verify users

A protocol for the transfer of files across the internet to the web server.[1] Users can access a server request that files be downloaded to them alternatively upload the file to the web server where they're stored.[1] 

• Organisation which has direct links to the internet and accepts transmissions from users over dial-up or broadband connection
• Most individual users of the internet access it though service providers e.g. Sky, BT etc.

An internet service provider has direct links to the internet and accepts transmission from users over communication lines passes these onto the internet.[1]  The ISP sells internet access to companies or individuals and provides access to web servers which connect to and search engines to the internet.[1] An ISP will provide the user with a range of services.[1]

• Application accessed over the internet, maintains the indexes of webpages
• Users wanting information on a particular topic will access the search engine using the internet and submit a topic of list of topics
• Search engine will compare this list with pages in it's index and generate a page of hyperlinks which the user can click to go to the desired web pages
• As most search engines index millions of page

A search engine is a web-based tool that searches for information using key words and criteria.[1] It will return results as website links based on the criteria provided.[1] Some use a spider or 'webcrawler'. This program 'crawls' through the web and contracts and index of pages based on Meta-data embedded in the head of the document.[1]

• Store of recently accessed webpages and the images they contain, kept by a brower.
• Transmitting more information than is strictly necessary over the internet is inefficient, if a user revisits a page that is already stored in the cache.
• Process has negatives, may be accessing the web regularly to see if there is anything.
• If page is reloaded from cache, will appear identical to the page on the last visit.
• Browsers allow cached files to be deleted periodically. 

Allows browsers to download website image, data and documents for faster viewing in the future.[1] A local of information is kept.[1] Means that the browser will be able to load at least some information from each page you have visited without downloading information again from server.[1] Decreases loading time.[1]    

• Small files placed on the hard drive of a user's computer by the website they visited
• Once obtained the website will not ask for them again, will keep them
• User can decline at any time

Small files downloaded to computer when visiting a website.[1] They can store previous activity on that site and user preferences.[1] Information can be used when user re-visits the site.[1]

• A portal is a websites designed to be the one that a user will want to visit first when accessing the web
• Obvious commercial advantages for a portal in attracting as many users as possible, advertise on site
• To be useful to the individual, site must offer services such as news updates and search engines
• In most cases user can personalise page

A website that acts as a main entry point to a group of web services.[1] Portal can require the user to login and provide a range of services such as emails, links to other websites and search engines.[1] e.g myschools

• A website is a collection of webpages at the same domain, often with a common theme and maintained by one person or company/organisation
• User moves between pages by clicking on hyperlinks
• Causes new page to load or old page to refresh

A page of information stored on the WWW [1] can contain sound, video, animation, graphics and hypertext as well as simple text [1] viewed using a web browser

• A 'document' accessed in a browser
• Generally contain text and graphics and may well contain audio or video
• Only text is stored on the webpages
• Others are loaded onto the page by users computer using URI (Uniform Resource Identifier)
• For large files e.g. video and audio, streaming may be used.

A collection of HTML pages linked together on the world wide web.[1]