The illuminated object lowered in Times Square at midnight on New Year's Eve is the Times Square Ball. Its descent is one of the world's best-known New Year's countdown rituals.
The first ball was lowered on December 31, 1907, replacing a fireworks display that could no longer be safely staged in the crowded area. Early versions used wood and iron and were lit with incandescent bulbs. Later designs became larger, brighter, and more technically elaborate.
The current ball is a geodesic sphere covered with Waterford crystal triangles and illuminated by LEDs. The design has changed over time, including special versions used for anniversary years and major public events.
A common mix-up is to call it the “New Year's Eve ball” without naming Times Square. Balls are also used in other countdowns, but “Times Square Ball” is the established name for New York City's landmark object.