constitution preamble: Amendment 22

Section 1. 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 some other person was elected President shall be elected to the office of the President more than once. But this article shall not apply to any person holding the office of President when this article was proposed by the Congress, and shall not prevent any person who may be holding the office of President, or acting as President, during the term within which this article becomes operative from holding the office of President or acting as President during the remainder of such term.

Section 2. This article shall be inoperative unless it shall have been ratified as an amendment to the Constitution by the legislatures of three-fourths of the several States within seven years from the date of its submission to the States by the Congress.

So the 22nd amendment just states that a president can't hold office for more than 2 terms, and only one term is he/she took office for longer than 2 years of the presidents spot they took. Basically there cannot be a president for longer than 10 years.
In the early part of 2009 there was talk of a bill going through Congress dealing with the repealment of amendment 22 and taking the limit off of the amount of terms a president can have. Personally I don't think that doing this is a good idea. If we didn't limit the amount of terms a president could have, it would be basically like a king running the country. One person always in charge. There could be one good president that holds office for 5 terms, and because of that a better candidate of the same party might not get a chance to run. America is always looking for change so I don't think that this bill has any chance and probably never will.