I have this very strange problem here. After I "make" a very simple piece of C codes, I received no errors; furthermore an executable file of that piece of codes was generated. But when I typed in the program's name, bash told me "program_name command could not be found." I am wondering what goes wrong to my computer / Linux. Then I tried this "hello world" programme, the same thing happned again.
May I have some help here please.