Chapter 5 - The Internet And Its Uses

World-wide interconnection of networks. Makes use of transmission control protocols and internet protocols. Stems from INTERconnected NETwork and is more of a concept that relies on physical infrastructure that allows individual devices and networks to connect to others.

World Wide Web Massive collection of webpages based on hypertext transfer protocols (HTTP/HTTPS). A part of the internet that can be accessed by users through web browser software and used to access information using the internet.

INTERNET: allows for emails to be sent and recieved Online messaging (text/audio/video) Makes use of TCP and IP World wide collection of interconnected networks and devices WWW: Web sources accessed by web browsers Collection of multimedia and other information on websites https is written using HTML (hypertext markup language) URLs are used to specify the location of web pages Uses the internet to access information from websources

Software that connects to the Domain Name Server to locate IP addresses. Interperets HTML pages sent to a users computer so that they can read documents and access multi-media. Allows user to access and display web servers on their screen. Show the translations of HTML

Uniform Resource Locators Text based addresses for websites/used to access websites

Protocol://website address/path/file name (Https://websitename.za/ict)

Domain host (www) Domain name(website name) Domain type(.org.net etc) Country code(.uk.za)

Hyper text transfer protocol Written with HTML Set of rules that must be obeyed when transferring files across the internet

Hypertext Tranfer protocol secure Some form of security (SSL/TSL) is being used. Extra security applied meaning a more secure way of sending and receiving data over a network

Make use of java script Allow the user to navigate forwards and backwards through previously opened pages Hyperlinks Home page Address bar Multiple tabs can be open at once Data stored as cache Bookmarks (store favourites) User history Cookies

Highlighted text or image activated by clicking that links to further text, photos or other webpages/websites

Written in HTML Hosted on a web server with its own IP address

The need for users to memorise IP addresses

Domain Name server Finds IP addresses for domain names given in URL from its large data base in which the URLs have matching IP addresses

• The user opens their browser and types in a URL code, and the browser requests the DNS find the IP address of the website. • DNS server 1 checks its data base and its cache, if it can’t find the URL it sends a request to DNS server 2 • DNS server 2 finds the file and can map it. So the IP address is sent back to DNS server 1 which puts the IP address and associated URL into its data base and cache • IP address is sent to users computer • The computer sets up communication with the website server and the required pages are downloaded. HTML files are sent from the website and are interpreted by the browser which displays the content on the users screen

Small files of text/code sent by a web server to a browser and stored on the users computer. Small lookup tablets containing (key,data) pairs that are used to track data such as IP addresses and browsing activity to maintain user preferences based on their previous activity. Can also be used to customise the webpage for the user

Session cookie

Session cookies Persistent/permanent cookie

Setting/options stored in cookies that can remember customised webpages/indicate browsing history to target adverts

Cookie that is temporarily stored on users computer and is deleted when the browser is closed or the session ends. Used for online shopping to store things in the users virtual shopping basket. Stored in temporary memory and dont collect any information from users computer nor personally identifies users.

Area of memory on a website that temporarily stores item a user wishes to purchase until a payment is made or the session expires.

Remove the need for users to type in login details every time a certain website is visited

So that they can authenticate a users browser

Cookies stored an users hard drive that are only deleted when the expiry date is reached or the user deletes it (or deactivated after 6 months due to countries laws). Effective way of carring data between website sessions and eliminating the need for large amounts of data to be stored on the server itself as well as the typing in of login details each time the website is visited. May only store personal information and user preferences if given consent by the user and legitamate websites will encrypt the personal information stored in a cookie.