When you search "hemoglobin" at PDBj site, you will find various types of molecule shapes in the search result list (Figure 1). The variety means the molecule may be folded into different form for each situation as well as the included atomic coordinates (asymmetric unit, AU) don't always equal to the biological functional unit (biological unit, BU) (Figure 2). Then I illustrated some examples of hemoglobin molecules. The Figure 3 shows two states of hemoglobin molecules from human: one is oxidized form, and the other is reduced form. Figure 4 shows two types: one is normal type, and the other is hemoglobin S which causes sickle-cell anemia. Finally I introduce another feature of PDBj search that the search target includes not only PDB entries but also PDBj websites, such as news, help and Molecule of the Month articles (Figure 5).