What is DNS?
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DNS (Domain Name System) is the internet's address book. It translates human-readable domain names like tidalmail.com into machine-readable IP addresses like 192.0.2.1, so computers can find each other across the internet.
Without DNS, you'd need to memorize numeric addresses for every server you wanted to reach. DNS makes that invisible and automatic.
For email senders, DNS does a lot more than just routing traffic. Your domain's DNS records are where receiving servers go to check whether your email is legitimate. When an email from captain@deepcurrent.io lands at someone's inbox, the receiving server runs DNS lookups to answer a few important questions before it even thinks about delivering the message.
Here's what DNS actually stores for email:
- MX records tell other servers where to deliver inbound mail for your domain.
- SPF records list which IP addresses are allowed to send email on your behalf.
- DKIM records publish the public key that receiving servers use to verify your email's cryptographic signature.
- DMARC records tell receivers what to do when an email fails SPF or DKIM checks, and where to send reports about those failures.
If any of those records are missing or misconfigured, your email can end up in spam or get rejected outright. DNS isn't just plumbing. It's the foundation that authentication and deliverability are built on.
Want to go deeper? The next question covers how DNS and email work together in more detail.
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