Why Microsoft built proprietary email protocols—and when standard ones aren't enough for how work actually happens.
POP3 downloads your email to one device. IMAP keeps it on the server so every device sees the same inbox. One philosophy won.
IMAP solved email's hardest problem: making one mailbox appear on every device. Your phone, laptop, and tablet aren't holding copies—they're windows into the same place.
The email protocol that treats your mailbox like a physical mailbox—you take the letters out and bring them home
The four SMTP ports exist because email's original design trusted everyone. Each port number tells the story of a problem that needed solving.
The 40-year-old protocol that still delivers every email you send—a polite conversation between servers that was designed when the Internet trusted everyone
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