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The Email Journey

1

1. Composition

User writes email in client (Gmail, Outlook)

2

2. Submission

Email sent via SMTP to outgoing mail server

3

3. Routing

DNS MX records direct email to recipient’s server

4

4. Delivery

Stored in recipient’s mailbox (IMAP/POP3)

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Key Components

MTA

Mail Transfer Agent (e.g., Postfix)

MDA

Mail Delivery Agent (e.g., Dovecot)

MUA

Mail User Agent (e.g., Thunderbird)