A dumbbell is a piece of exercise equipment used for strength training. It typically consists of a short bar with weights attached at both ends. Dumbbells come in various sizes and weights, allowing users to perform a wide range of exercises targeting different muscle groups. Dumbbells are versatile and can be used for both upper and lower body workouts. They are commonly found in gyms and can also be used at home. Many people use dumbbells to improve their strength, endurance, and overall fitness, making them a popular choice for both beginners and experienced athletes.