I has been working with Windows OS many years. I think that small tips are useful for Windows users who start learning Linux.
  1. Names and commands are case sensitivity.
  2. File name should not contain spaces.
  3. "/" is a root directory.
  4. File name starting with a dot "." is a hidden file.
  5. There are no DOS-style drive letters.
  6. A line starting with # is a comment.