Acute and chronic renal failure are discussed. Acute renal failure is a sudden decline in kidney function leading to a build-up of waste products and electrolyte imbalances, with symptoms like reduced urine, nausea, and back pain. It requires urgent hospital treatment like dialysis. Chronic renal failure is a gradual loss of kidney function over years due to issues like diabetes and hypertension, with symptoms including fatigue, itchy skin, and twitching. Diagnosis involves tests of kidney function and size, and treatment focuses on managing symptoms and slowing disease progression with medications.