Quantum Computing For Dummies

Chapter 2

Looking Back to Early and Classical Computing

IN THIS CHAPTER

Examining early efforts at computing

Tracking the rapid rise of today’s computers

Combining classical and quantum computing

Why talk about classical computers — the laptop and desktop computers, tablets and smartphones, web servers, and even the world’s largest supercomputers, all of which people depend on every day — in a book about quantum computing? Three reasons, really.

The first is that quantum computers handle only certain specialized tasks, which means they'll never fully replace classical computers. You'll use classical computers to set up and initiate quantum computing jobs, and you’ll receive the results via classical computers. So using quantum computers requires using classical computers.

Second, the best way to understand quantum computing is by comparing it to classical computing. So having a firm grasp on the history and progress of classical computing will help you to understand what’s so special about quantum computing.

Finally, many of the most challenging tasks for quantum computers will require a hybrid operation, with classical computers and quantum computers handling specific steps in ...