TXT record
TXTA TXT record holds free-form text. In practice it carries domain verification tokens and email authentication policy.
What a TXT record is for
A TXT record attaches arbitrary text to a name. DNS itself assigns no meaning to the contents — the meaning comes from whatever reads it.
Most TXT records in practice do one of two jobs: proving to a third party that you control a domain, or publishing email authentication policy such as SPF and DMARC.
Character strings and the 255-byte limit
A TXT record is made of one or more character strings, and each string is limited to 255 bytes. A longer value is split across several strings within the same record.
Readers are expected to concatenate those strings with nothing between them. A value split in the wrong place, or joined with a space, produces a policy that looks right in a dashboard and fails in practice.
Multiple TXT records at one name
Unlike a CNAME, a name may carry many TXT records, which is why several verification tokens can coexist on one domain.
Some consumers require exactly one matching record, though. A domain must publish at most one SPF record, and two is a configuration error rather than a redundancy.