The CAN-SPAM Act sets baseline rules for every commercial email to or from US recipients: truthful headers, working opt-out, physical address, no deceptive ...

Canada's Anti-Spam Legislation (CASL) is the strictest commercial email regime in North America: opt-in consent required before the first message, working ...

The General Data Protection Regulation is the anchor of European privacy law and the default framework for every marketing sender reaching an EU recipient. ...

Reference catalog of 68 email protocol RFCs. Tiered by importance: essential standards every sender must know, complete reference catalog, and historical ...

Defines the structure of email messages: headers, body, encoding, and field syntax.

Previous email message format standard. Obsoleted by RFC 5322 in 2008.

The original email message format standard from 1982. Historical foundation of all subsequent format RFCs.

The authoritative SMTP standard defining the full MTA-to-MTA command sequence.

Original SMTP RFC from 1982 by Jon Postel. Defined the core SMTP command set still in use today.

The earliest email transfer protocol RFC, predecessor to SMTP.