MX records, or Mail Exchange records, are a type of DNS (Domain Name System) entry that specifies which mail servers are responsible for receiving email messages on behalf of a domain. When someone sends an email to an address at your domain, mail servers use MX records to determine where to deliver the message. Each MX record includes a priority value, allowing multiple mail servers to be listed for redundancy and load balancing. Properly configured MX records are essential for ensuring reliable email delivery and protecting against email-based cyber threats, such as spoofing or phishing. Incorrect MX records can result in lost or undelivered emails.