To do so, it will pick off the first element of the list — the head — to do the processing on that element, and recursively pass the rest of the list to itself again.

A structural element can be a subsystem, a process, a library, a database, a computational node, a legacy system, an off-the-shelf product, and so on.

Turn the burner off once the milk is boiling, but leave the saucepan on the element or gas grate.