Hi Amit,
The Participant data is used if you want to record something against a participant and then use it again later. An example from the Set Participant Data action resource center article: "In contrast to flow variables, participant data attributes persist between transfers from one flow to another. For example, the participant's telephone number (Call.Ani) does not persist if the interaction transfers to another flow. But if you store the information into participant data, other flows can access that data."
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Sam Jillard
Online Community Manager/Moderator
Genesys - Employees
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