Snakes use several senses to sense their surroundings. They have excellent eyesight, which helps them to detect movement. They also have a strong sense of smell, which helps them to locate prey and detect predators. Additionally, they have a special organ called the 'Jacobson's organ', which allows them to detect chemicals in the air and gives them a sense of taste. Finally, they have sensitive receptors in their skin that help them detect vibrations in the ground.