People are often confused between the Internet, the World Wide Web, Domains and Emails. This article will hopefully demystify these mysterious mysteries.
Firstly, what is the difference between the Internet and the World Wide Web? (Just for fun, see if you can answer this question before reading the information below.)
The Internet is certainly not a little black box with a red light on top! (The IT Crowd – Series 3 – Episode 4: The Internet).
The Internet is a physical and global connection of computers. The World Wide Web is a collection of millions of websites that you access via the Internet.
The Internet is millions of computers connected with “wires”. These “wires” are mostly underground or under the sea and are often in the form of fibre-optic cables for speed. At the end “of the line” we have good old copper wire running into your home and this part of the line is unfortunately quite slow. It is like competing in a race with a nitroglycerin charged racing car and then using a bicycle near the finishing line! Unless you’ve got a digital connection piped straight into your house – often referred to as cable.
These days the Internet can also be transferred “through the air” which is known as Wi-Fi. If you access the Internet via Wi-Fi in your house you are either doing it over the mobile phone network with a Wi-Fi dongle USB’ed into your computer or from a Wi-Fi modem in your house. This Wi-Fi modem is connected to the Internet via the previously mentioned “wires” and then beams the Internet through air to your computer. It is the same with your smart phone or tablet.
Side note – The way things are going these days it’s not going to be called the mobile phone network any more, it’s probably going to be called the mobile data network!
This global network of connected computers transfer information like websites, emails, FTP (transferring files from a computer to a server), instant messaging and a few others which are not important to list here.
The World Wide Web
In the early years, the Internet allowed a computer to talk to another computer, but this was a specific one-to-one link between computers. It was created by ARPANET within the US Department of defence. Tim Berners-Lee [allow tremendous trumpet fanfare here!] wanted to create an automated distributed document system and created HTTP to do that. HTTP is Hypertext Transfer Protocol, which means text in a digital document which has links that can link you to another digital document.
With this system people could jump from document to document using a computer that was connected to the Internet so that they could access those documents. He called it the World Wide Web and today we access websites on this web.
Let’s take a quick look at the components of a domain:
Computers manage to keep the World Wide Web neatly sorted out with IP addresses. A typical IP address is 18.104.22.168; which is the IP address of www.brainstormadvertising.co.uk. We humans, however, much prefer easy-to-remember names to find a website. I don’t give 19.16 8.48.7 as my website address, Iof course advertise it as www.brainstormadvertising.co.uk. It is just like giving someone your address in words of house number, street, suburb, postal code and country rather than the latitude and longitude. DNS (Domain Name System) servers, the world over, are the machines that link IP addresses to domain names.
In a domain, www.brainstormadvertising.co.uk, the Top Level or First Level domain occurs in the suffix, for example .co.uk. org, .com, .biz, .net and so on. Then we have the Second Level Domain, which is owned by organisations like cnn.com or brainstormadvertising.co.uk. You can also have subdomains like www.curiosity.brainstormadvertising.co.uk (no, don’t click on that. It doesn’t go anywhere).
When you type www.brainstormadvertising.co.uk into your web browser, a message is sent to a Resolving Name Server to ask what exact IP address belongs to brainstormadvertising.co.uk. This computer is often your own ISPs Resolving Name Server. Within seconds the Resolving Name Server looks through its cache to find the correct IP address. If it is not in its cache, the Resolving Name Server will ask other root and name servers for the answer. Once it knows the IP address of brainstormadvertising.co.uk, it sends that information straight back to your browser. Your browser then connects with the server computer at the ISP that has that IP address and “asks” for the website files. The server computer sends the website files to your browser, which has the technology to display the website that you are looking for.
How does this relate to your email?
Whenever you send an email, it is sent from a Sender Workstation. This is your computer where your email software like Microsoft Outlook, Apple Mail, Thunderbird email and various other email software is installed. You use the email software to send, receive, organise and store your emails.
Your email then goes to an SMTP server. SMTP stands for Simple Mail Transfer Protocol. A protocol is a set of communication rules that computers follow so that they can communicate. The SMTP server “asks” a DNS server where it should send this email. The DNS server looks at the domain name and then gives the IP address back to the SMTP server. The SMTP server then sends it to the ISP (Internet Service Provider) that is hosting the domain of the person that you’re sending the email to.
Your email is then stored by your receivers ISP. Please note, that you never send an email directly to someone’s computer, you send the email to their server and the receiver will receive the email when they download their emails using their email software. This is of course the Receiver Workstation.
You receive emails using POP or IMAP protocol in your email software. The difference between POP and IMAP is that with a POP account you download your emails from the server onto the device. IMAP is more like a cloud service where your emails stay on the server and that leaves you free to access you emails from many different devices. Obviously we do not have email addresses based on IP addresses; imagine if my email was email@example.com – try advertising your business with those numbers! Your email software is tuned into relying on Domain Name System servers to send your email to the right person. Look at the diagram below:
I do hope that this is demystified the mystery of the Internet and how it is put together. Please feel free to comment below. Happy Interneting!