Story
A short, simple description of functionality told from a user's perspective — the smallest planning unit in SAFe.
User Story format ("As a <role>, I want <feature>, so that <benefit>") popularized by XP. Scrum doesn't mandate the format. LeSS and Nexus use Product Backlog Items, which may or may not be user stories.
Across the Frameworks
Scrum
Informal*User Story* as optional format.
SAFe
Native*Story* (formal team-level artifact)
LeSS
InformalProduct Backlog Items may take story form.
Nexus
InformalUsed colloquially, not framework-defined.
Related Terms
Present in Scrum, SAFe, LeSS, Nexus.