Phage display comprises an array of methods, which can be used to display proteins on bacteriophages. We present in this article a summary of techniques, which can be used to express antibody libraries on bacteriophages. Since many researchers are more familiar with the conventional hybridoma technique for production of monoclonal antibodies we describe analogies and differences between these two techniques, both of which are used to reach comparable scientific objectives. We focus on the features which are specific to phage display techniques rather than for hybridoma techniques. These comprise the freedom to choose other animals than the mouse for immunization, the enormously large sample (up to 10(9) clones) which can be drawn and immortalized from a single immunized animal and the opportunity to enhance affinity of isolated antibodies by in vitro affinity maturation. The panning techniques, which are used to enrich specifically binding phage antibodies from the huge libraries are briefly summarized.