Glossary
Short, plain definitions of the words you meet when you run a website, a domain name or business email.
W
- What is a DMARC record?
- A DMARC record is a TXT record at _dmarc.yourdomain.com that tells receiving email servers what to do when a message claiming to be from your domain fails SPF and DKIM checks: deliver it, send it to spam, or reject it. It also asks them to send you reports on who is sending as you.
- What is an MX record?
- An MX (mail exchange) record is a DNS setting that tells the internet which mail server receives email for your domain. Each record has a priority number and a server name, and senders try the lowest number first. If your MX records are missing or wrong, email sent to your domain can't be delivered.
- What is an SPF record?
- An SPF record is a TXT record on your domain that lists which mail servers are allowed to send email using your domain name. Receiving servers check it to spot forgeries. Each domain can have only one SPF record, and it must stay within 10 DNS lookups or it stops working.
- What is DKIM?
- DKIM (DomainKeys Identified Mail) adds a hidden digital signature to every email you send. Your email provider signs each message with a private key, and you publish the matching public key in your domain's DNS. Receiving servers use it to confirm the email came from your domain and wasn't changed on the way.