Atomic requirements (ATR) are primarily, 'well-formed requirements' ANSI/IEEE Standard 1233-1998 . Well-formed requirements' are are abstract, unambiguous, traceable and ventidatable (testable). In addition to being well-formed requirements, ATRs are also responsible for splitting complex requirements into elementary, or indivisible, requirements. Usually, an ATR takes the form of a single sentence using non-formal language, nevertheless precisely expressing a specification.
The chances are considerably better to achieve un-ambiguity with a set of ATRs than with an equivalent, non-atomic specification . The implications of the ATR notion are wide, encompassing requirements and design specifications since both are documented in a similar way , and since a specification at any abstraction level can be viewed as both requirement and design[5,9]. Indeed, atomic requirements (ATRs) have demonstrated their benefits in the hi-tech industry  when were used to document data processing application in software requirements specifications documents, as well as in individual programs' detailed design documents.