This essay provides an overview of climate change during the Quaternary period, also known as the Pleistocene, which began approximately 2 million years ago. It examines the cyclical nature of glacial and interglacial phases, highlighting the expansion and contraction of ice sheets. The essay delves into the various factors influencing these cycles, including ocean currents, the carbon cycle, astronomical changes, and greenhouse gases. It also explores the impact of plate tectonics, volcanic eruptions, and ocean currents on climate change. Furthermore, the essay discusses the effects of climate change, such as the formation of lakes, isostatic adjustments, and the influence of winds and ocean currents. It also touches upon the impact on megafauna and the current warming of the oceans. The study references various sources to support its claims and provides a comprehensive understanding of the Quaternary period's climate dynamics and their implications.