Shannon Applecline's Designers & Dragons: A History of the Roleplaying Game Industry
is a massive history book (the page count clocks in at 442) on the origins, growth, and development of tabletop roleplaying games, from the beginnings of TSR to the indie revolution. It is the product of years of research and interviews, presented in a very accessible style, making no assumptions on the reader.
The PDF covers the history of the hobby chronologically, but gives the reader the opportunity to explore at the end of each section, where there are short lists labeled "What To Read Next." Each of these lists present the reader with related games, companies, play styles, and other subjects from the previous section that may have caught the reader's interest, allowing the opportunity to either visit another section of the book, or forge ahead to the next one. It's subtly similar to choose-your-own adventure books, and gives the reader the sense of control and exploration that comes with actually playing the games that the book is devoted to.
Designers & Dragons takes us from the early days of TSR, Flying Buffalo, and Judge's Guild, through the turmoil of the satanic panic era of the 1980s and AD&D's second edition, past the CCG and D20 eras, and into today's indie revolution and retroclones. It is a fitting chronicle to our hobby, and I'm dying to have a dead-tree edition to put on my shelf with my other reference books.
Check out Designers & Dragons at DriveThruRPG