Tax

9/10 people take the standard deduction, which is a fixed amound (based on income?).

Itemized deductions are more accurate, but require much more record keeping.

The IRS has a pay as you go system and requires businesses to submit estimated quarterly taxes that are finalized in their annual return. When employees declare dependencies in their W-4, taxes are calculated and paid for them by the employer. Employees only need to submit an annual return with their W-2, along with any other info, and often get a return amount.