A moisture sensor is a device that detects the amount of moisture in the soil or air. It works by measuring the electrical resistance or capacitance, which changes based on the moisture level. These sensors are commonly used in agriculture, gardening, and environmental monitoring to ensure optimal moisture levels for plants and crops. Moisture sensors can be simple handheld devices or more complex systems integrated into automated irrigation systems. They help users make informed decisions about watering, reducing water waste, and promoting healthy plant growth. Many modern sensors can connect to smartphones or computers for real-time monitoring and data analysis.