The travel guidebook has been a trusty companion for travelers since ancient Rome, but the future of the print guidebook is seriously imperiled by smartphone apps and digital books. This neat infographic (see below) from the travel booking website Cheapflights chronicles the long and useful history of the print travel guidebook. Check it out:
Travel Between The Pages 
Great little chart! I really hope that guidebooks continue into the future, there is something so nice about holding the book and writing notes on the pages. Also, how will they overcome dodgy Internet and electricity outlets in the rougher parts of the world? Long live the humble guide-book I say!