The application is aimed at students from high school to graduate school as well as all curious people. We currently show the cell and the earthworm but other organisms will be added soon. The principle is to visualize biological structures and to learn to identify the different parts with the help of 3D and list boxes. The main interest is to make the link between theory (the 3D object) and practical observations (real objects from histology). The user can thus take advantage of the 3D structures to understand figures usually given in courses and in textbooks. The data correspond perfectly with the courses generally taught in this field. In the earthworm, it is also possible to understand the organization of the main systems through the visualization of different cross-sections, and it helps to understand these different section. The application also provides (in French and English) explanatory texts for the different structures.