Page "Workflow" Paragraph 49

Components can only be plugged together if the output of one previous ( set of ) component ( s ) is equal to the mandatory input requirements of the following component.

Thus, the essential description of a component actually comprises only in-and output that are described fully in terms of data types and their meaning ( semantics ).

The algorithms ' or rules ' description need only be included when there are several alternative ways to transform one type of input into one type of output – possibly with different accuracy, speed, etc.