According to the Kronos Workforce Central 6.3 Developer's Reference Guide, one of the required properties when running a <HyperFindQuery> is QueryPersonOrEmployee.
RunQuery
Returns a list of people and associated information for the specified HyperFind query.
Return Value Type: Zero or more HyperFindResult tags
Required Properties: HyperFindQueryName, VisibilityCode, QueryDateSpan, QueryPersonOrEmployee
The Action Descriptions section states that the possible values for QueryPersonOrEmployee are Person, Employee, and Job Assignment.
QueryPersonOrEmployee
Category (person, employee, job assignment) for queryThe type of person being requested in the query
Type: String
Optional
Enumerated value: Person, Employee, Job Assignment
As far as I can tell, this is the only part of the API which makes any distinction between a Person and an Employee. I was under the assumption that both terms were interchangeable in Kronos.
What is the difference between a Person and an Employee in Kronos Workforce Central?
Everyone is a person but not everyone is an employee. Employee's have an employee license while if a person simply has a manager/web license then they are not an employee.