We don't know how operating systems accomplish their goals. What does it mean when we speak about a "operating system?"

How does a supercomputer differ from a mainframe computer?

Assume that you must take a computer-programming language course next semester. How would you decide which language would be best for you to study? Do you think that a professional programmer needs to know more than one programming language? Why or why not?

Software companies are continually improving programming languages. Would learning a programming language in grade school provide you with skills that you would need more than a decade later when you enter the workforce? Why or why not?