Final answer:
Diuretics are compounds that increase urine output and are used to treat hypertension, congestive heart failure, and fluid retention. Alcohol and caffeine also act as diuretics.
Step-by-step explanation:
A diuretic is a compound that increases urine output and therefore decreases water conservation by the body. Diuretics are used to treat hypertension, congestive heart failure, and fluid retention associated with menstruation. Alcohol acts as a diuretic by inhibiting the release of ADH. Additionally, caffeine, when consumed in high concentrations, acts as a diuretic.