A configuration is the position of a kinematic structure. For example a person sitting, standing or posing in some way would be a configuration. In STEP terms this is called a configuration_definition. Specifically the standard says: "A configuration_definition specifies a configuration of a kinematic_structure in terms of pair parameter sets. A kinematic_pair defines the kinematic constraints between two adjacent links coinciding at a joint."
Select the base the man is standing upon to watch the interpolation between several pre-defined configurations. In other words make this guy walk!