1. A computer-implemented method for expressing information comprising the steps of: extracting attributes of a plurality of data objects, wherein the attributes reflect information associated with the data objects; hierarchically grouping the data objects based on the attributes of the data objects to form a hierarchical structure; establishing basic representation units, wherein the basic representation units include multimedia attributes and each basic representation unit corresponds to at least one data object; establishing a mapping relationship between distinct attributes of the data objects and the multimedia attributes of the basic representation units; displaying the basic representation units to reflect the hierarchical grouping of the data objects on a multimedia device, wherein the mapping relationship is used to determine the multimedia attributes of the displayed basic representation units; and providing a group of interactive operations to permit interaction with the displayed basic representation units, wherein the interactive operations comprise: changing the mapping relationship between attributes of the data objects and the multimedia attributes of the basic representation units; filtering to screen data objects according to specified filtering criteria; and drilling down to a lower level of the hierarchical structure or rolling up to higher level of the hierarchical structure, wherein the drilling down and rolling up functions adjust the scope of data object expression.