You know, don't push the button, don't push the button, don't push the button, and then some socko finish. I was pleasantly surprised by how the book bobs and weaves and is a lot more active and entertaining that just that. MILD SPOILER, so don't tell your four year old.
The late payment penalty applies to any portion of your federal tax that remains unpaid as of the due date, typically the tax filing date. The IRS imposes a failure-to-pay penalty of one half of one percent for each month or part of a month that the tax goes unpaid.
1 Under the health care law, you must have qualifying health coverage or pay a fee on your next federal tax return.  The penalty in 2016 is 2.5% of household income or $695 per adult (half of that per child), whichever is higher. Learn more about the fee for not being covered.