A little less jargon.
Useful email terms, explained in the context of the decisions they support.
Short definitions, with a route into the full explanation. Provider-specific details and technical concepts are referenced in the linked guides and source library.
Spam
Unwanted email. It can include unsolicited promotions or abusive messages; not every unwanted message is necessarily a phishing attempt.
Explore spam filtering ↗Phishing
A deceptive attempt to obtain information or induce an unsafe action by impersonating a trusted person, organization, or service.
Understand phishing checks ↗False positive
A legitimate message incorrectly classified as spam. Investigate the result and verify the message before correcting it.
Review misplaced mail ↗False negative
Spam that is not classified as spam. A low-risk label is not a guarantee that every request inside a message is safe.
Read about classification errors ↗Classification threshold
A decision cutoff used to convert a score into a classification within a defined system. Different cutoffs change which items are flagged.
Understand scoring thresholds ↗SPF
A mechanism for a domain to publish which systems are authorized to send using the relevant envelope domain identity.
Read the authentication guide ↗DKIM
A domain-associated digital signature that can be checked against a published public key. It is not the same as message encryption.
Understand DKIM ↗DMARC
A mechanism connecting authentication to the visible From domain through alignment, with policy and reporting capabilities.
Understand alignment ↗Label
A category used to organize messages. Provider implementations differ; Gmail labels are not identical to traditional folders.
Build an organization system ↗Archive
An action that can remove mail from the inbox while retaining the message. In Gmail, archived mail remains available in All Mail.
Read the archive example ↗Inbox rule
A set of matching conditions and actions used to organize or handle messages. Personal rules are separate from a provider’s full filtering system.
Build careful filters ↗Independent verification
Confirming a request through a known route that does not rely on the questionable message itself. This is a suggested security-review habit.
Explore verification habits ↗