DNS is the address book for your domain. These records are the ones clients most often see:

• A: points a name to an IPv4 address.
• CNAME: points one name to another hostname.
• MX: tells mail servers where to deliver email.
• TXT: stores verification and email security values such as SPF, DKIM, and DMARC.
• NS: shows which nameservers control the DNS zone.

Do not delete old records until you know what they do. Removing email or verification records can interrupt service.