💻 Computers

An email's journey

A message travelling from a computer to a server, then to another server, then to the inbox

📖 In short

You write a message to your grandmother and press “Send”, and seconds later it reaches her inbox in another city. But the message doesn't jump straight from your computer to hers: it passes through many stops, like a paper letter going through the post office, the van and the postman.

🤩 Did you know?

  • If you type the address wrong, the server sends the message back to you with a note saying it couldn't find the person.
  • The “spam” folder collects messages the server thinks are ads or tricks.
  • The same message can be sent to many people at the same time.
  • Emails can stay stored on servers for many years.

🔎 Find out more

🌟 1. Writing and sending

You write the address, subject and text, then press “Send”. The email program takes your message and sends it to your “mail server”, which is like the post office in your neighborhood.

🔍 2. Finding the address

Your server looks at what comes after @ in your grandmother's address, then asks the internet directory: where is the mail server for this name? And it gets its address.

💡 3. Travelling across the internet

The message is split into small packets that travel through routers and cables, perhaps each by a different route, then they all come together at your grandmother's mail server.

🎯 4. The inbox

Your grandmother's server keeps the message in her inbox even if her computer is off. When she opens her email, her program asks the server for new messages, and your message appears!

🧭 Return to sender

If the server can't find the person, it sends you an automatic message saying the message didn't arrive. Check the address letter by letter, because one small mistake is enough to lose it.

🌈 A check before it arrives

Before the message reaches the inbox, the receiver's server checks it: does it have a virus? Does it look like a trick message? If it's suspicious, it goes into the “spam” folder.

📊 See how it works

The message's journey: from your computer to your mail server, across the internet to your grandmother's mail server, then into her inbox
The message's journey in five stops, from your computer to the inbox.

📚 Key words

Mail server
A computer that sends and stores messages
inbox
Where new messages go
Packet
A small piece of the message

🧪 Try it at home

Act out the message's journey: put signs saying “your computer”, “your mail server”, “the internet”, “Grandma's mail server” and “inbox” in rooms around the house, and carry an envelope from stop to stop, explaining what happens at each one.

🧩 Test yourself

1 Where does the message wait until your grandmother opens her email?

2 What happens if you type the address wrong?

📚 Read next

🎮 Try it yourself