One of the Primary Framing Devices of an Alternate History, Textbook is a compromise between Narrative and Timeline. In the Textbook style, the story is a "history book" (or series of newspapers, or interviews, etcetera) from ATL. This style allows the author the most freedom in writing without blatantly drawing comparisons to OTL and using AH terminology. There are drawbacks, though. Starting the timeline on the PoD may seem strange, as would going into greater detail post-PoD after just summarizing the events before.