Hot aisle containment is a cooling strategy used in data centers to improve energy efficiency. It involves enclosing the hot aisles, where servers expel warm air, to prevent this hot air from mixing with the cooler air in the cold aisles, where servers intake air. This separation helps maintain optimal temperatures for the equipment. By using physical barriers, such as walls or curtains, hot aisle containment directs the flow of air more effectively. This system reduces the workload on cooling systems, leading to lower energy consumption and costs while enhancing the overall performance and lifespan of the servers in the data center.