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The internet, the web and IP addresses
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The internet and the World Wide Web are not the same thing. This lesson unpicks how a web page reaches your screen.
Internet and WWW
The internet is the global network of networks: the cables, routers and connections.
The World Wide Web is the collection of web pages and websites accessed over the internet.
Web pages are written in HTML, stored on web servers, and fetched using HTTP or HTTPS. An ISP (internet service provider) gives you access to the internet.
A URL is a web address, such as https://www.example.com/news.html: protocol, domain name, then the path to the page.
The World Wide Web is the collection of web pages and websites accessed over the internet.
Web pages are written in HTML, stored on web servers, and fetched using HTTP or HTTPS. An ISP (internet service provider) gives you access to the internet.
A URL is a web address, such as https://www.example.com/news.html: protocol, domain name, then the path to the page.
DNS and IP addresses
DNS (Domain Name System) translates a domain name like www.example.com into the IP address of the server.
Addressing standards mean every device uses the same format, so data can be delivered anywhere.
IPv4: 32 bits, written as four denary numbers 0 to 255, such as 172.16.254.1. That gives 232, about 4.3 billion addresses: not enough.
IPv6: 128 bits, written as eight groups of four hexadecimal digits separated by colons, giving vastly more addresses.
Addressing standards mean every device uses the same format, so data can be delivered anywhere.
IPv4: 32 bits, written as four denary numbers 0 to 255, such as 172.16.254.1. That gives 232, about 4.3 billion addresses: not enough.
IPv6: 128 bits, written as eight groups of four hexadecimal digits separated by colons, giving vastly more addresses.
Getting connected
You type www.example.com into a browser. Put these in order: browser requests the page with HTTPS; DNS finds the IP address; web server sends the HTML.
- First, DNS translates the domain name to an IP address.
- Then the browser requests the page from that address using HTTPS.
- Finally the web server sends back the HTML.
Answer: DNS lookup, HTTPS request, server sends HTML
The internet is the network; the WWW is pages accessed over it. DNS turns domain names into IP addresses. IPv4 is 32 bits (four numbers 0 to 255); IPv6 is 128 bits in hex. Modems, routers, switches and WAPs connect us.
The interactive lesson includes the diagrams for this topic.
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