A dishwasher is a device that can automatically clean cups, dishes, and utensils. Its function is to use hot water and detergent to clean cups and utensils, thereby achieving sterilization, disinfection, and hygiene. The benefits of a dishwasher include:

1. Convenience: Using a dishwasher can save the trouble of hand washing cups, and multiple cups and utensils can be washed at once, saving time and effort.
2. Health and safety: A dishwasher can thoroughly clean cups and utensils with hot water and detergent, killing bacteria and viruses, ensuring the safety and hygiene of food.
3. Energy saving: A dishwasher can automatically control the use of water temperature and electricity, which is more energy-efficient than hand washing cups.
4. Environmental protection: A dishwasher can reduce water usage and the use of detergent, thereby reducing its impact on the environment. In short, a dishwasher is a convenient, hygienic, energy-saving, and environmentally-friendly cleaning device that can bring many benefits to people's lives.