Phony Make Targets

It is often necessary to make things that are not files, a make target that does not create a file is a phony target.

clean:
    rm -rf temp

.PHONY: clean

As the target clean does not create a file of the same name, we mark it as phony by adding it to the special .PHONY target. A phony target will always run the command even if a matching file exists.