Abstract: Method to visualize the information related to a catalog on an processing device (2) that includes a user's interface comprising a display (3). The method includes a looking through step of a database (11) that stores an E-catalog of items that can be purchased by use of said device (2). At logic-content level the database is organized according to the hierarchical tree-type structure (15) wherein the items that can be purchased are the leaf nodes (T1, . . . T5) of the tree and the groups of items are the intermediate nodes of the tree placed at different hierarchical levels that are higher than the hierarchical level of the leaf nodes.