A vent, or outlet, is an opening that allows air, gas, or other substances to flow in or out of a space. Vents are commonly found in buildings, where they help regulate temperature and improve air quality by facilitating ventilation. They can be part of heating, ventilation, and air conditioning systems, often referred to as HVAC systems. In addition to buildings, vents are also used in various appliances, such as stoves and dryers, to expel heat or moisture. Proper venting is essential for safety, as it prevents the buildup of harmful gases, ensuring a healthier environment for occupants.