kb/data/developer.mozilla.org/en-US/docs/Glossary/SMTP-0.md

title	chunk	source	category	tags	date_saved	instance
SMTP - Glossary | MDN	1/3	https://developer.mozilla.org/en-US/docs/Glossary/SMTP	reference	web, html, css, javascript, documentation	2026-05-05T05:43:51.819448+00:00	kb-cron

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1. Glossary
2. SMTP

SMTP

SMTP (Simple Mail Transfer Protocol) is a protocol used to send a new email. Like POP and NNTP, it is a state machine-driven protocol. The protocol is relatively straightforward. Primary complications include supporting various authentication mechanisms (GSSAPI, CRAM-MD5, NTLM, MSN, AUTH LOGIN, AUTH PLAIN, etc.), handling error responses, and falling back when authentication mechanisms fail (e.g., the server claims to support a mechanism, but doesn't).

In this article

• See also

See also

• SMTP (Wikipedia)
• Related glossary terms:
  • NNTP
  • POP
  • protocol
  • state machine