Kids, don't try this at home. Writing a book takes personal sacrifice, including many hours staring at your monitor while just knowing htat noboday will actually read this, execpt your relatives. And even then it becomes obvious that they'll nod their heads with a vacuous look on their faces and say, "Clustering what? Does that include Nougat in some fashion?"
Have you ever noticed that the system administrator's job seems to have two states applied to it? That they're either ignored or hated.