immunoglobulin are produce by the body against specific stimuli i.e antigen. antibody are of different types and these are classify according to there nature, temperature of reaction, structure and crossing of placenta. antibody are of Y shaped structure which is composed of different region. classification is based on the type of heavy chain, there are 5 major classes of antibodies, IgA, Igd, Igm, ige, most important of these are igm and igg, although each and every have there own significance.