HDL test measures the level of HDL cholestrol in blood. High-density lipoprotein (HDL) also called as the "good" cholesterol is one among the group of lipoproteins which enable lipids like cholesterol, triglycerides and other fats to be transported within bloodstream. They help to remove cholesterol from artery walls. It is then carried to the liver where it breaks down and is eventually removed or excreted from the body in the bile. HDL cholesterol is therefore considered the "good" cholesterol. The higher the HDL cholesterol level, the lower the risk of a heart attack, stroke, or other cardiovascular problem. It is a part of Lipid Profile. It is always advisable to go for complete profile, as level of each test in profile are considered while making decision on diagnosis as well as monitoring the treatment. Lifestyle changes, including exercising, keeping weight within recommended limits, and giving up smoking can increase the body's levels of HDL cholesterol.