The Hodgkin lymphoma (HL) is a B-cell lymphoma, as was proved by molecular studies with single-cell PCR. Histologically, it is characterized by a minority of neoplastic cells, Reed-Sternberg cells and its variants, related to a variable non-neoplastic inflammatory background. Nowadays, (WHO classification) the following types of HL are recognized: Nodular Paragranuloma and the Classical Hodgkin Lymphoma, the latter including Nodular Sclerosis, Mixed Cellularity, Lymphocyte-rich Classical Hodgkin Lymphoma and Lymphocyte Depletion. Morphology together with immunohistochemical studies allows to classify the different forms of Hodgkin lymphoma and to make a differential diagnosis with non-Hodgkin lymphomas. All classical Hodgkin lymphomas are treated similarly, and chances for remission and survival are currently good. Molecular parameters should be added to the current classification and patients could benefit from new therapeutic targets.