In a given rule: foo.o : foo.c $(CC) $(CFLAGS) -o $@ $< The "$@" is the output (or target, think of @ as a bullseye on a target), and the "$<"

In a given rule: foo.o : foo.c $(CC) $(CFLAGS) -o $@ $< The "$@" is the output (or target, think of @ as a bullseye on a target), and the "$<" is the input (think redirection). The only other commonly used variable is "$^": foo : foo.o util.o other.o $(CC) $(LDFLAGS) -o $@ $^ $(LDLIBS) In this case, "$^" means "all inputs".