A method for exploring a catalog of digital information contents through a user apparatus is provided with a display screen, in which the catalog of digital information contents is structured according to at least two hierarchical tree structures, each including a respective hierarchy of nodes, each node corresponding to a respective category of digital information contents. The method includes: selecting a first sub-hierarchy of nodes of a first one of the at least two hierarchical tree structures, the first sub-hierarchy of nodes being built beginning from a selected category of the first hierarchical structure by selecting at least one among a first number of categories at immediately higher hierarchical levels in comparison to the selected category and a second number of categories at immediately lower hierarchical levels in comparison to the selected category; selecting a second sub-hierarchy of nodes of a second one of said at least two hierarchical tree structures, the second sub-hierarchy of nodes being built beginning from a destination category of the second hierarchical structure, the destination category being in relationship with the selected category, by selecting at least one among a first number of categories at immediately higher hierarchical levels in comparison to the destination category and a second number of categories at immediately lower hierarchical levels in comparison to the destination category; displaying on the screen icons representative of the categories of the first and of the second sub-hierarchy and respective relationships between the categories; and exploring the categories of the first and of the second sub-hierarchy reacting to commands imparted by the user through said user apparatus.