IgM is often the first antibody produced in an infection that is later 'released' by IgG and with its ten binding sites is an excellent immunoglobulin for the capture of antigens.
IgG is produced in larger quantities or with repeated contact with the antigen (virus). The IgG molecule can be regarded as a typical antibody. The presence of IgG antibodies shows whether you have experienced the disease in question.
IgA is found in mucosal (mucosal) secretions and produced in the gut. It is present in the gastrointestinal organs (intestine, stomach), prostate, respiratory epithelium and in low concentrations in the blood. With IgA deficiency, there are too few or no IgA antibodies in the blood. This can give a false negative result.