2.1 Some basic questions you should think about

  1. What are the fundamental differences between Windows, Linux, UNIX and OS X operating systems?
  2. Why doesn’t a program on one operating system run on another?
  3. What about platform-independent applications such as Java or HTML?
  4. What is the difference between a .png and .jpg file?
  5. Is one better than the other?
  6. What is the difference between a .txt and .xlsx file?