How Do Computers Add? Part 2

Have you ever wondered how computers and calculators—both of which are nothing more than mindless boxes of plastic, wires, and other strange parts—manage to add numbers? And so quickly! Math Dude has the second part of the story.

Jason Marshall, PhD
4-minute read
Episode #146

After weeks of learning about binary numbers, Boolean algebra, and the math that makes the tiny electronic components known as logic gates tick, we’re finally ready to begin tackling the big questions we’ve been working towards: How do computers and calculators add? And how do they do it so quickly? I’m happy to say that those are exactly the questions we’ll be answering today..

Review: Logic Gates

As we talked about last time, the key to building machines that can add are something called logic gates. These tiny electronic components perform Boolean operations on one or more input bits and spit out a binary output bit as the result. So far we’ve learned about three fundamental logic gates that implement the AND, OR, and NOT operations of Boolean algebra. But are there others? In particular, are there any other logic gates that are useful for building machines that can add?


About the Author

Jason Marshall, PhD

Jason Marshall is the author of The Math Dude's Quick and Dirty Guide to Algebra. He provides clear explanations of math terms and principles, and his simple tricks for solving basic algebra problems will have even the most math-phobic person looking forward to working out whatever math problem comes their way.