DNS
What is Domain Name System (DNS)?
The global directory that maps domain names to IP addresses and stores the records that govern email routing and authentication.
DNS is a distributed, hierarchical database that resolves human-readable domain names into IP addresses and serves record types such as A, MX, TXT, and CNAME. Email delivery and authentication depend on DNS because receiving servers look up MX records to route mail and TXT records to verify SPF, DKIM, and DMARC. Changes propagate according to each record's TTL, so edits are not always instant.
Why it matters for cold email
Every deliverability control for cold email lives in DNS, so a missing or mistyped record silently routes mail to spam. Correct DNS configuration at your registrar or DNS host is the foundation that SPF, DKIM, DMARC, and custom tracking domains all build on.
Related terms
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