18 min read

Email

Email addresses, how a message travels between mail servers, SMTP, IMAP and POP3, and using email safely and professionally.

An Email Address

An email address has two parts joined by @ : orders@ceylonleaf.lk orders — the mailbox (the user name). ceylonleaf.lk — the domain whose mail server holds the mailbox. A business email on its own domain looks more professional than a free address, and staff can change without the address changing.

1 You write a message in an email client (Outlook, Gmail, a phone mail app). 2 The client sends it to your outgoing mail server using SMTP (Simple Mail Transfer Protocol). 3 Your server uses DNS to find the recipient's mail server, and passes the message on with SMTP. 4 The message waits in the recipient's mailbox. 5 The recipient's client collects it using IMAP or POP3 .

IMAP vs POP3

$IMAP$	$POP3$
$Messages stay on the server; every device shows the same mailbox$	$Messages are downloaded to one device and usually removed from the server$
$Best for people who use a phone and a laptop$	$Best for one computer with poor internet access$
$Read on your phone \to shows as read on your laptop$	$Each device has its own separate copy$

Warning signs of phishing: urgent threats, spelling mistakes, a sender address that does not match the organisation, requests for passwords or OTP codes, and unexpected attachments. Never share an OTP (one-time password) — banks never ask for it.

Practice

The tea room emails a newsletter to 150 customers. Which field should hold their addresses?

How Email Travels

1 You write a message in an email client (Outlook, Gmail, a phone mail app). 2 The client sends it to your outgoing mail server using SMTP (Simple Mail Transfer Protocol). 3 Your server uses DNS to find the recipient's mail server, and passes the message on with SMTP. 4 The message waits in the recipient's mailbox. 5 The recipient's client collects it using IMAP or POP3 .

IMAP vs POP3

$IMAP$	$POP3$
$Messages stay on the server; every device shows the same mailbox$	$Messages are downloaded to one device and usually removed from the server$
$Best for people who use a phone and a laptop$	$Best for one computer with poor internet access$
$Read on your phone \to shows as read on your laptop$	$Each device has its own separate copy$

Email Features

Using Email Safely

Warning signs of phishing: urgent threats, spelling mistakes, a sender address that does not match the organisation, requests for passwords or OTP codes, and unexpected attachments. Never share an OTP (one-time password) — banks never ask for it.

Practice

The tea room emails a newsletter to 150 customers. Which field should hold their addresses?