History is about the written record. In any given society, time that passed before the development of writing is pre-history in that sense. In western culture that can go back thousands of years, in some uncontacted, isolated tribes, pre-history is ongoing. The study of the past isn't limited to history, it includes archaeology, geology, genetic studies, and a few more (especially if you want to go further back than the dawn of humanity).

In German, the term for history is "Geschichte", which can mean both history and story, things that are told (originally that which has happened, "was geschehen"). There are similar facets in English history, in the Latin historia and Greek ἱστορία: Inquiry, Science, History, the knowledge gained by one's own insight, the report, tale, historiography.

One important aspect in that is the tale, the story. Without it, there is no history, there are only those events that occured before humans had stories that could endure until our times. It's a more fundamental way to relate to our ancestors, since we can not only study what they left behind in a material sense, but also, however remote, something of what they thought and said, the stories they told. That is to me, philosophically, a large part of what history is about.

The primary scientific separation between pre-history, early-history and history (ancient, medieval, modern and so on) is that pre-history works completely without written sources, early and ancient history has written sources, but has to rely on archaeological evidence to get a somewhat clear picture of events, while history uses primarily written sources, relying on disciplines like archaeology to flesh out the picture. This is very idealized, in practice it becomes, as always, pretty fuzzy and muddled on the edges.

In history you can get knowledge from two kinds of sources: remains and from tradition. Remains are simple physical evidence that we can study to find out about the past (e.g. ruins, records). Tradition is something that was deliberately created to tell about history. This means mainly historical writing. The whole later is lacking before writing was invented. (history probably existed a little longer, but no oral records have survived that long).