Zocor is a type of statin. Statins are cholesterol-lowering medicines. They may be used to treat a high level of cholesterol in the blood due to lifestyle factors such as a high-fat diet or not doing enough exercise of familial hypercholesterolaemia, a high level of cholesterol in the blood due to inheriting a gene that causes your liver to make lots of cholesterol
In some cases, Statins may also be used to reduce the risk of having a heart attack or stroke.
Definition from NHS Choices: Zocor