Glossary
Delegation
Delegation lets one principal authorize another to act on its behalf for a defined purpose, while the record of what happened still shows both identities: who delegated, and who acted under that delegation. Done well, delegation is auditable and revocable independent of the underlying identities involved.
The scope of a delegation matters as much as the fact of it: a delegation that grants everything the delegator could do is functionally the same as handing over the delegator's own credentials, with none of the containment a narrower, purpose-specific delegation would provide.