A filibuster is a political tactic used in the United States Senate to delay or block legislation. It allows a senator or a group of senators to speak for an extended period, often for hours or even days, to prevent a vote on a bill. The goal is to prolong debate and give opponents time to gather support or negotiate changes. To end a filibuster, the Senate can invoke cloture, which requires a supermajority of 60 votes. If successful, cloture limits further debate and allows the Senate to proceed to a vote on the legislation. This process highlights the balance between majority rule and minority rights in the legislative process.