A vapor bubble is a small pocket of vapor that forms within a liquid when the liquid is heated or experiences a drop in pressure. This phenomenon occurs when the local pressure around the liquid decreases, allowing the liquid to boil at a lower temperature. Vapor bubbles can be found in various applications, including cooking and industrial processes. When a vapor bubble forms, it can grow and collapse, creating a process known as cavitation. This can lead to significant effects, such as erosion in pumps and propellers. Understanding vapor bubbles is essential in fields like thermodynamics and fluid mechanics.