Here:
History is a subject. And from the questions being asked, that should give you some understanding and clues of what the term 'History' means.
History is the study of human past occurences or the study of human eventuality and involvement. It is the study of olden days, historical events including yesterday.
The American Revolution happened long ago, and thats why it is part of History. The Dinosaurs died millions of years ago, it is still part of history. The Titanic ship sank some years back, it is still part of History.
Now you know what History means.
Hopefully this helped! :D :D