A vacuum pump is a device that removes gas molecules from a sealed volume to create a vacuum. It works by creating a pressure difference, allowing air and other gases to be drawn out. Vacuum pumps are commonly used in various applications, including laboratories, manufacturing, and medical equipment. There are different types of vacuum pumps, such as rotary vane pumps and diaphragm pumps, each designed for specific tasks. These pumps can achieve varying levels of vacuum, making them essential for processes that require low pressure, such as freeze-drying and vacuum packaging.