Analysis of information sources in references of the Wikipedia article "Function (computer programming)" in English language version.
We could supply our assembling clerk with copies of the source code for all of our useful subroutines and then when presenting him with a mainline program for assembly, tell him which subroutines will be called in the mainline [...]
Callable unit: (Of a software program or logical design) Function, method, operation, subroutine, procedure, or analogous structural unit that appears within a module.