Looking for a "Mainframes for Beginners" book? Need to learn about z/OS fast? Then this is the book you need. This is the perfect introduction to IBM zSeries Mainframes and z/OS. Avoiding technical jargon, it gives you the basic facts in clear, light-hearted, entertaining English. You'll quickly learn what Mainframes are, what they do, what runs on them, and terms and terminology you need to speak Mainframe-ese. But it's not all technical. There's also invaluable information about the people that work on Mainframes, Mainframe management issues, new Mainframe trends, and other facts that don't seem to be written down anywhere else. What On Earth is a Mainframe is the closest you'll get to a "Mainframes for Dummies" book. Programmers, managers, recruitment consultants, and industry commentators will all find this book their new best friend when trying to understand the Mainframe world.