# Glossary

- [ESP](/glossary/esp): Email service provider: software for sending, templating, and often automating email.
- [AI-native ESP](/glossary/ai-native-esp): An email platform built around brand-aware generation and agent operation, not a bolted-on writing assistant.
- [SPF](/glossary/spf): Sender Policy Framework: DNS record listing hosts allowed to send for a domain.
- [DKIM](/glossary/dkim): DomainKeys Identified Mail: cryptographic signature that proves message integrity.
- [DMARC](/glossary/dmarc): Policy layer telling receivers what to do when SPF/DKIM fail, plus reporting.
- [Deliverability](/glossary/deliverability): The practice of earning inbox placement through authentication, reputation, and engagement quality.
- [Transactional email](/glossary/transactional-email): Messages required to complete a user action or account process.
- [Lifecycle automation](/glossary/lifecycle-automation): Event-driven email flows tied to product and customer stages.
- [MJML](/glossary/mjml): A markup language that compiles to responsive email HTML.
- [MCP for email](/glossary/mcp-email): Model Context Protocol servers that let AI agents operate email platforms.


Canonical: https://emailmarketing.sh/glossary

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