There has been some talk recently of a possible government shutdown if Republicans take over Congress and pass appropriations bills that the President vetoes.

So, what is a veto and how does it work? A veto is a constitutional process by which the president can object to a piece of legislation passed by Congress and prevent it from becoming law.

A standard veto occurs when the president returns a piece of legislation to Congress with an explanation of why he or she has declined to sign the bill into law.

Congress can override a veto with a vote of two-thirds majority in each chamber.

The President can also veto a bill by simply refusing to sign it within 10 days of receipt. This is called a pocket veto. Congress must be out of session for a pocket veto to take hold. If Congress is in session and the President holds a bill without signing it for 10 days, the bill automatically becomes law.