What history books lack

History books differ from one country to another; not just by the language its written in, but by the content. A person would thinks a history book has every single historical event that occured in the past, they are mistaken. Some countries tend to leave out some negative events or information due to their dislike or ashame because it does not really reflect a good image on them. By not mentioning their loses or defeats, they either do not get into detail or just fail to mention it. That ofcourse has its disadvantages because students will be unaware of some important historical events and details and they will have wrong ideas about them and not know the truth behind every thing that had happened in the past.