WRITING COMPUTER CODE
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Library of Congress Control Number: 2016941390
ISBN 978-1-119-17730-2 (pbk); ISBN 978-1-119-17732-6 (ebk); ISBN 978-1-119-17733-3 (ebk)
SO, YOU WANT TO GET STARTED WRITING REAL COMPUTER CODE! Maybe you’ve played with drag-and-drop programming languages or you’ve done modding in Minecraft, and you’re ready for the next level. Great! There are currently more than 500 different languages for coding on computers (which isn’t very many, when you consider that there are about 6,500 human languages!). You’re about to learn the most popular languages that are used by millions of coders all over the world.
In this book, you’ll learn to use HTML5, CSS3, and JavaScript to create programs for computers. More people have used these three computer-coding languages than any other coding language that’s ever been invented. In fact, every single website that you visit makes use of these three languages. That’s why we think you’ve made a great decision by beginning your journey into the world of coding by picking up Writing Computer Code.
Computer code is fun and easy to learn. With some determination and a lot of imagination, you’ll be creating your very own computer programs in no time!
Just as the only way to become a great athlete or musician is to practice, practice, practice, the only way to become a computer programmer is to write code, write code, write code!
This book is put together as a series of projects with steps for constructing each project from start to finish. The projects also build upon one another, so that by the end of the book you’ll have an animated robot that you can control with your mouse and continue to modify and improve long after you finish all the projects.
Here’s what you need to do the projects in this book:
As you work through each project, keep in mind the following:
www.dummies.com
, to visit that website.http://jsfiddle.net/user/watzthis/fiddles
. If you want to check your work, or just copy ours, be sure to look at both of these.We already know that you’re ready and willing to code. Because you’re reading this, we know you’re fully qualified and able to get started right away. We don’t make many assumptions, but here are the things we wanted to mention upfront:
That’s really all there is to it. If you get stuck, keep in mind that many problems in writing computer code happen simply because of spelling errors or words that you type that a computer can’t understand. Proceed slowly and carefully, and you’ll do great!
As you read through the projects in this book, you’ll see a few icons. The icons point out different things:
Once you take your first steps down the road of writing code, the world of computers will open up to you and you’ll be able to use your computer to do some pretty amazing things. You’ll also join the community of millions of programmers around the world as we shape the web and the future! Congratulations on taking the first step!
PROJECT 1
COMPUTERS CAN’T DO THINGS ON THEIR OWN. They need a computer program to tell them what to do, and they need people to write those computer programs. The people who write the code to make computers do all sort of things are called computer programmers.