LDL, also known as low density lipoproteins is bad cholesterol that is usually produced by the liver. Low density lipoproteins carry lipids and cholesterol from liver to diverse areas of the body, like muscles, tissues, organs, and the heart.
One important thing to be known about low density lipoproteins is that efforts need to be made to keep these down as if they increase their prescribed limits; chances are that the blood stream is getting more than required cholesterol.