ZVW wg: employer’s portion that Exactpi pays for the Health Insurance Act.
WW wn: employee portion that you pay for the Unemployment Insurance Act.
Payroll tax: withholding tax for the income tax that Exact withholds for you and pays to the tax authorities.
ZVW wn: income-related employee portion that you pay for the Health Insurance Act.
Net wage: your wage after deduction of taxes and social security contributions. So this is what you have earned net.