Write  a paper about the operating systems you know  the ones you used.  Describe these operating systems’ functions and usage scopes and some usage scenaries.  (写一篇关于知道的操作系统有哪些？用过的操作系统有哪些？描述一下这些操作系统的功能和使用范围，应用场景)

For the desktop operating system I know the DOS