To download data files from an information transmission side computer to an information reception side computer by automatically classifying the data files into a hierarchical structure.

Data files are classified into a hierarchical structure, and the classification information is applied to each data file, and a data base including the group of the data files and download operation guidance information are stored in a first computer. At a second computer side, the download operation guidance information is received from the first computer, and displayed on a display, and the data files to be downloaded are selected based on this, and the selection information is transmitted to the first computer. At the first computer side, the pertinent data files are extracted from the data base based on the selection information, and distributed to the second computer. At the second computer side, the classification information of the data files received from the first computer is analyzed, and the data files are classified into the hierarchical structure based on this classification information and stored.