H/t @dirvine for this, and a topic for discussion of the IPNS or Interplanetary Naming System
This is a Wiki so feel free to edit, add links, improve the summary etc.
Here are the docs:
Summary
IPNS defines a mutable record, or pointer to IPFS content, and even to content on other protocols such as Safe Network. These records are verifiable and versioned, much like the earlier Safe Network Naming System.
This is a technical specification for the records, referenced by names, which is I think a misnomer [cough] because these are not human readable names in the way we are accustomed to in conventional DNS and SNNS. I infer that because an IPNS name is the hash of a private key.
I guess an app layer could provide human readable naming, but this DNS App would not be universal even across IPNS, unlike the SNNS which provided secure, versioned, human readable decentralused naming across Safe Network.
IPNS is a way for these records to be self validating, so you can be sure they are signed by the expected private key corresponding to the owner. By using the hash of a private key in preference to a human readable name, IPNS is able to down multiple protocols (unlike SNNS).