According to the 22nd Amendment to the United States Constitution, no person can be elected to the office of the President more than twice. This means that a President can serve a maximum of two four-year terms.

Prior to the 22nd Amendment, there was no term limit for the President. Franklin D. Roosevelt was elected to four terms, but he died during his fourth term in office.

The 22nd Amendment was ratified in 1951, after Roosevelt’s death. It was passed in response to concerns that a President could become too powerful if they were allowed to serve more than two terms.

The 22nd Amendment also includes a provision that allows a person who becomes President without being elected to serve a full term. This provision was included to address the situation where a Vice President becomes President due to the death or resignation of the sitting President.

For example, if a Vice President becomes President after two years of the sitting President’s term, that Vice President can serve two full terms of their own. However, if a Vice President becomes President after more than two years of the sitting President’s term, that Vice President can only serve one full term of their own.

The 22nd Amendment has been controversial since it was ratified. Some people believe that it is a violation of the people’s right to choose their own leaders. Others believe that it is necessary to prevent any one person from becoming too powerful.