so i am doing research into what a shell is and i found this wikipedia article https://en.wikipedia.org/wiki/Shell_(computing)






and it says "In computing, a shell is a computer program which exposes an operating system's services to a human user or other program."






my question is, "exposes an operating system's services to a human user or other program." what does the "other program" mean? i understand that it acts as an interface between the human user and the operating system, but i don't understand the "other programs" part

thanks