1. A system for collaboration among a plurality of users, each at a respective one of a plurality of computing appliances having input apparatus to provide an input and having display apparatus to provide a display presentation, the system comprising: mapping logic defining a mapped structure for non-transitory storage of data in a plurality of separate data layers a memory, wherein each said data layer is comprised of from one to a plurality of parts, wherein each said user is associated with an associated said data layer and with the parts thereof; input logic permitting each of at least two said users to concurrently provide an input that is associated with the user via a respective said input apparatus, wherein each said input provides associated said user data representative of an image; storage logic storing the user data in the data layers associated with the user providing the input, responsive to the mapping logic; display definition logic selecting for each of at least two of the users, at least one of the parts for each said user to be selected parts of the data layer that is used to generate an associated image that is representative of the selected parts of the data layer to provide an associated display layer, wherein each said display layer has an associated display priority; display generation logic, generating a combined display presentation by combining the associated images for the display layers, wherein the associated image for a first said display layer appears within the combined display presentation positioned as one of underneath of and atop of the associated image for a second said display layer, responsive to the display priority of each of the first said display layer and the second said display layer, wherein the combined display presentation is provided for viewing to at least one of the users.