The off-diagonal cells are used to indicate relationships between the elements. A marking of the cell indicates a directed link between two elements and can represent design relations or constraints between product components, communication between teams, information flow or precedence relations between activities. In one convention, reading across a row reveals the outputs that the element in that row provides to other elements, and scanning a column reveals the inputs that the element in that column receives from other elements. For example, in the DSM, the marking in column A and row C indicated a link from A to C (output from A, input to C). Alternatively, the rows and columns may be switched (without a change of meaning). Both conventions may be found in the literature.