Glossary

Glossary

Plain-English definitions for the standards, metrics, and mechanisms behind email exits and inbox triage.

Glossary

Clean Inbox: What It Actually Means (a Working Definition)

A clean inbox is one where every message has been decided on and the intake is curated — a state you reach, not a count you chase. Here's the full definition.

5 min read
Glossary

Graymail: Bulk Email That May or May Not Be Wanted

Graymail is bulk email whose value depends on the recipient — newsletters, promos, and alerts that may be wanted or unwanted. Learn how providers classify it and what to do.

4 min read
Glossary

List-Unsubscribe Header: What It Is and How It Works

The List-Unsubscribe header (RFC 2369) tells your mail app how to unsubscribe you, and powers Gmail's unsubscribe button. Here's the plain-English anatomy.

5 min read
Glossary

RFC 8058: The One-Click Unsubscribe Standard, Defined

RFC 8058 is the IETF standard for one-click email unsubscribe: an HTTPS POST via the List-Unsubscribe-Post header — no login, no confirmation page.

6 min read
Glossary

Sender Reputation: Definition, Signals, and Why It Matters

Sender reputation is a provider-specific assessment associated with a sending domain or IP. Compare Gmail, Microsoft, and third-party views without treating them as one score.

6 min read
Glossary

Spam Complaint Rate: Definition and the 0.3% Threshold

Spam complaint rate is a provider-defined share of measured mail recipients report as spam. Gmail and Yahoo publish 0.3% risk thresholds with different measurement contexts.

6 min read
Glossary

What Is Email Triage? Definition and How It Works

Email triage is the fast sorting of incoming email by what each message needs — reply, archive, unsubscribe — before any of that work begins.

4 min read