5.1 - Internet and WWW

Internet - A large global network [WAN] allowing users to access the world wide web [It is an infrastructure]

WWW - World Wide Web - Collection of all the websites and web pages that can be accessed using the internet

5.2 - Requesting & Retrieving Web Pages

URL [Uniform Resource Locator] - Fundamental component of the WWW - Text based address for a website

Structure :

Protocol - a set of rules for formatting and processing data.

DNS - Domain Name Server -

• Server that stores domain names + their IP addresses
• Many DNS’ [billions of pages] - if one DNS cannot find IP, it sends to the next one. If not found, a message is sent back to browser

Process of requesting and retrieving web pages :

1. Opens browser and types URL into address bar
2. Web browser sends URL for website to DNS [Domain Name Server]