Cholesterol is a waxy substance found in the bloodstream and body tissues. High levels can increase risk for heart disease and stroke. Cholesterol comes from two sources - it is produced by the liver and absorbed from food. There are different types, with LDL or "bad" cholesterol increasing risk when high, and HDL or "good" cholesterol lowering it. Lifestyle factors like diet, exercise, weight, and smoking can impact cholesterol levels. Medication may be needed if levels remain high despite lifestyle changes. Proper management is important for cardiovascular health.