1. A system for accessing digital media files representing audio and/or visual information, each file being associated with at least one tag characterizing at least one aspect of the nature of said information, the system comprising: at least one data storage configured to store media files, an input interface configured to receive operator-generated commands, an output interface configured to present graphical representations of the media files on a format comprehensible to a human user, and a data processor configured to: organize the media files according to a hierarchical structure based on the at least one tag associated with each file, and cause the output interface to present information reflecting said structure, the structure comprising a top-level layer and a bottom-level layer, the top-level layer containing a two-dimensional layout of at least two category segments, each category segment being associated with one or more of the media files, each category segment representing an area delimited by a number of edges, and each category segment adjoining at least one other segment along at least one of its edges, an edge between a first category segment and a second category segment designating that the media files associated with the first category segment are different from the media files associated with the second category segment with respect to at least one disparity criterion, the category segments being organized such that the media files included in adjacent category segments are more similar to one another than the media files included in non-adjacent category segments, the bottom-level layer comprising a graphic representation of an individual file of the media files, receive the operator-generated commands, and in response thereto cause the output interface to present an adjusted graphical representation of the media files, determine an intensity parameter reflecting a frequency at which each media file has been reproduced relative to the other the media files included in the hierarchical structure, and assign the contents of at least one of the at least one variable data field in response to an intensity parameter.