This book teaches the basics of computer programming. It’s meant for kids, but anyone who wants to learn how to program a computer can use it.

You don’t need to know anything about programming to use this book, but you should know the basics of using your computer. Maybe you use it for email, surfing the Web, listening to music, playing games, or writing reports for school. If you can do the basic things on your computer, like starting a program and opening and saving files, you should have no trouble using this book.

What you need

This book teaches programming using a computer language called Python. Python is free, and you can download it from several places, including this book’s web site. To learn programming using this book, all you need are

• this book (of course!).
• a computer, with Windows, Mac OS X, or Linux on it. The examples in this book are done in Windows. (There is some help for Mac and Linux users on the book’s web site: www.helloworldbook.com.)
• basic knowledge of how to use your computer (starting programs, saving files, and so on). If you have trouble with this, maybe you can get someone to help you.
• permission to install Python on your computer (from your parent, teacher, or whoever is responsible for your computer).
• the desire to learn and try things, even if they don’t always work the first time.

What you don’t need

To learn programming with this book, you don’t need

• to buy any software. Everything you need is free, and a copy is available on the book’s web site, www.helloworldbook.com.
• any knowledge of computer programming. This book is for beginners.

Using this book

If you’re going to use this book to help you learn programming, here are a few pointers that will help you get more out of it:

• follow along with the examples
• type in the programs
• do the quiz questions
• don’t worry, be happy!

Follow along with the examples

When you see examples in the book, they’ll look like this:

Always try to follow along and type the programs in yourself. (I’ll tell you exactly how to do it.) You could just sit in a big, comfy chair and read through this whole book, and you’d probably learn something about programming. But you’ll learn a whole lot more by doing some programming.

Type in the programs

The installer program that goes with this book will copy all the example programs to your hard drive (if you want). The installer is on the book’s web site:www.helloworldbook.com. You can also view and download individual examples from the web site, but I encourage you to type as many of them yourself as possible. Just by typing the programs, you’ll get a “feel” for programming and for Python in particular. (And we can all use more typing practice!)

Do the quiz questions

At the end of every chapter, there are some questions to practice what you’ve learned. Do as many as you can. If you’re stuck, try to find someone who knows about programming to help you. Work through them together—you’ll learn a lot by doing that. Don’t peek at the answers until you’re done, unless you’re really, really stuck. (Yes, some of the answers are in the back of the book and on the web site, but like I said, don’t peek.)

Carter says

I wanted to make sure this book was good for kids—fun and easy to understand. Luckily, I had some help. Carter is a kid who loves computers and wants to learn more about them. So he helped me to make sure I got this book right. When Carter noticed something funny or unusual, or something that didn’t make sense, we show it like this:

Note to parents and teachers

Python is a free, open source software, and there is no danger installing and using it on your computers. You can get the Python software—and everything else you need to use this book—for free at www.manning.com/helloworld.

The download files are simple to install and use and are free of viruses and spyware.

Books like this used to come with CDs with all the software on them, but now most readers (and publishers) prefer to use the Internet. If you can’t download the software from the book’s web site, Manning can send you a CD containing the same files available on the web site. There’s no cost for the CD, but you’ll have to pay the shipping and handling fee based on your address.

To get the CD, send an email to support@manning.com with subject line “Hello World! CD.” If you don’t have email, you can send a fax (609-877-8256), or a good, old-fashioned letter to:

Hello World CD Request
Manning Publications Co.
Planetarium Station
PO Box 347
New York NY 10024