Payroll inputs are simply the details necessary to set up an employee in the payroll system. These are items such as their name, date of birth, marital status, pay rates, vacation time, holidays, etc.
"Payroll inputs are all of the 'ins' that go into a payroll cycle. This includes time/hours, commissions, paid time off (holiday, vacation, sick, etc.), bonuses and any other variables or forms of payment."