Final answer:
If the president does not sign a bill within 10 working days and Congress is adjourned, it results in a pocket veto. If Congress is in session, the bill becomes law without a signature.
An outright presidential veto sends the bill back to Congress, allowing them to attempt a two-thirds vote override.
Step-by-step explanation:
After a bill passes Congress, it is presented to the president for review. If the president finds the bill unacceptable and takes no action on the bill after 10 working days while Congress is adjourned, the result is a pocket veto.
If the president takes no action after 10 working days while Congress is in session, the result is that the bill automatically becomes a law without the president's signature.
If the president vetoes the bill outright, the result is the bill is sent back to Congress, and they can attempt to override the presidential veto with a two-thirds vote in both the House and the Senate.