Final answer:
The 22nd Amendment establishes that no individual can be elected President more than twice and that anyone who serves more than two years of another's term may only be elected once more.
Step-by-step explanation:
The 22nd Amendment of the United States Constitution explicitly outlines the limitations on presidential terms. According to the Amendment, which was proposed and passed following the four-term tenure of President Franklin D. Roosevelt, no person shall be elected to the office of the President more than twice, and no person who has held the office of President, or acted as President, for more than two years of a term to which someone else was elected President shall be elected to the office of the President more than once. This was done to ensure a rotation in the leadership and to prevent a concentration of power. As an important note, this Amendment does not apply to any person holding the office of President at the time of the Amendment's proposal by Congress, nor does it prevent someone acting as President during the term within which the Amendment becomes operative from completing that term.