Final answer:
A presidential signature on a bill or joint resolution indicates the President's approval and the enactment of that legislation into law. A veto is the President's rejection of a bill, while an executive order is a separate action taken by the President.
Step-by-step explanation:
The presence of a presidential signature is an indication that a bill has been approved by the President and is now enacted into law. This could apply to a Congressional act or a joint resolution that has been passed by both houses of Congress. When the President signs a bill, it can become a new law, separate from issuing an executive order or vetoing a bill. If the President opposes a bill, they have the option to veto it and return it to Congress with objections. An override of a presidential veto requires a two-thirds majority vote in both Houses of Congress. For cases where a bill is not signed within ten days and Congress is in session, the bill automatically becomes law. Signing statements may accompany a signed bill, reflecting the President's views on its enforcement.