What is the difference between Graves’ disease and Hashimoto’s disease?

Both Graves’ disease and Hashimoto’s disease are autoimmune thyroid disorders where the immune system inappropriately targets the thyroid gland. However, they have opposite effects on thyroid hormone production. The autoantibodies produced in Graves’ disease cause the thyroid gland to overproduce thyroid hormones, leading to hyperthyroidism, while autoantibodies produced in people with Hashimoto’s disease cause significant injury and fibrosis of the thyroid, suppressing thyroid hormone production and leading to hypothyroidism.