"Snowball Earth" refers to a hypothesis suggesting that during certain periods in Earth's history, the planet was entirely or nearly entirely covered in ice. This phenomenon is believed to have occurred during the late Precambrian era, around 700 million years ago. The extreme glaciation likely resulted from a combination of factors, including reduced greenhouse gas levels and changes in solar radiation. The Snowball Earth events are significant because they may have influenced the evolution of life. As the ice eventually melted, it created new habitats and conditions that could support diverse organisms. This transition is thought to have played a role in the emergence of complex life forms, paving the way for the Cambrian explosion.