A/B Testing
Testing two (or more) variations of an email element (e.g., subject line, content, CTA, send time) to see which drives better results.
A record
A DNS record that maps a hostname (domain/subdomain) to one or more IPv4 addresses.
Address book/Safe Senders List
A recipient-managed list of trusted senders in their mailbox (a personal allowlist) that helps route approved mail to the inbox.
Alias address
An alternate email address that forwards mail to a primary mailbox, often used for privacy or organization.
Allowlist
A list of approved senders/addresses/domains that should be allowed through filtering (i.e., not blocked or routed to spam).
Allowlist/whitelist/Safelist
An organization- or admin-managed list of approved senders (email addresses, domains, and/or IPs) allowed to deliver to users’ mailboxes with reduced filtering.
Apple Mail Privacy Protection (MPP)
An Apple Mail feature that preloads tracking pixels via proxy, masking IP/device data and inflating open-rate tracking for some recipients.
Apple MPP
Apple Mail Privacy Protection: an Apple Mail feature that preloads tracking pixels via proxy, masking IP/location and inflating open tracking for some recipients.
Authentication
Verifying that an email is legitimately sent from a domain. Common methods: SPF, DKIM, and DMARC (which builds on SPF/DKIM alignment and policy).
B2B and B2C
Business-to-business (B2B) and business-to-consumer (B2C) sales/marketing models and audiences.