This document discusses osteoporosis, an age-related disease characterized by low bone mass and structural deterioration. It affects millions and causes debilitating fractures. There are two types: primary, which is more common with no direct cause and usually affects postmenopausal women; and secondary, which has an underlying illness as the cause, like leukemia or Cushing's syndrome. The author chose this topic to better understand this complex disease and how bone resorption and rebuilding become imbalanced over time.