Abstract: A data display, preferably having screens or windows, is built from data in a data base according to a hierarchy of display knowledge. Therefore, the data values themselves are separate from the knowledge or rules that specify how the data values are displayed to a user. In particular, the display knowledge is arranged in a hierarchy so that an individual item of display knowledge may be applicable to a wide range of data values representing the attributes of a number of different objects. In many cases, the range of data values or the attributes which the data values represent can be changed without any need to change the display knowledge. In other cases, only minor changes to the display knowledge are needed to properly display values for new or different data. These minor changes, for example, need only be made by changing the lowest level in the hierarchy of the display knowledge or associating items of display knowledge in the lowest level with different display knowledge in the higher levels.