System and method for transferring thematic information over the Internet in which graphical representations for different themes are created in a vector format, the vector graphics are imported into the frames of an animation movie, the frames of the movie are downloaded from the server to the client, and the frames are selectively overlaid to display different themes. The movie comprises a menu and a plurality of overlays that can be accessed by selecting topics on the menu. The menu file is downloaded first, and then data files for the overlays are downloaded in sequence. If the client selects a topic before the data file associated with it has been downloaded, the download is interrupted, and the data file for the selected topic is downloaded immediately.The amount of data that must be downloaded for thematic maps is minimized by downloading the outline of the region as a separate frame or overlay, and using that overlay with the overlays for a number of different themes. Where the maps include colored areas, the amount of data which must be downloaded is further reduced by extending the colored areas beyond the boundaries of the map to a simple polygon, then using the outline as a mask to display only the portions of the colored areas within the boundaries.Some maps include icons which represent links to locations on the Internet which have video clips with information relating the areas where the icons are displayed. When those icons are selected, the video clips are downloaded and played.