Apolipoproteins are divided into six major classes and several sub-classes. The classes are labeled A through H and the sub-classes are designated with specific numbers. For example, in apolipoprotein class A there exists apo A1, apo A2, apo A4 and apo A5. All are different and distinct apolipoproteins.
Notice in the table below that the same apolipoprotein can be found on different lipoprotein particles. Also notice that particles can have multiple apolipoproteins. This list is not comprehensive but illustrates some of the major apoliproteins associated with lipoprotein particles.