The bladder is a hollow, muscular organ in the body that stores urine produced by the kidneys. It is located in the lower abdomen and can expand and contract as it fills and empties. When the bladder is full, it sends signals to the brain, indicating the need to urinate. Urination is the process of releasing urine from the bladder through a tube called the urethra. The bladder plays a crucial role in the body's waste management system, helping to maintain fluid balance and remove excess waste. Keeping the bladder healthy is important for overall well-being.