Article 368 of the Constitution lays down the procedure for amending its provisions. A Constitution Amendment Bill can be introduced in either House of Parliament and must be passed by each House separately with a special majority—a majority of the total membership of that House and a majority of not less than two-thirds of members present and voting.
For amendments affecting federal provisions, such as the distribution of legislative powers or representation of states, ratification by at least half of the state legislatures is additionally required before the Bill is presented to the President for assent.
For exam purposes, aspirants should distinguish between amendments passed by simple majority, special majority, and special majority with state ratification, as this trichotomy is frequently tested in UPSC Polity.