Cross reference. A tool for helping understand a program that lists which classes/methods/variables use which
classes/methods/variables. They answer questions such as: Which classes does this class use? Which classes use
this class? Where does this method get called? Who references this variable? Who changes this variable? The
problem with paper XREFs (CrossReferences)
is they are out of date before they have finished printing. What you really want is a
SCID that lets you do such ask such questions dynamically on up to the second indexes
just by right clickking on a class, method or variable name.