Now, our antibody is also known as our immunoglobulin, where immuno means our immune system and globulin means our protein. So immunoglobulin is written with the following two letters IG. And we'll see that there are actually five different types of immunoglobulins. We have IGD we have IGA IgM IgG and we have Ige And each one of these five different types of antibodies carry out a different type of mechanism. They function in a slightly different way to basically carry out the function of defending our human cells, our body cells, from these pathogenic invasions. Now, what about the structure of these antibodies?