how to use this book: Intro
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Note
In this section we answer the burning question: “So why DID they put that in a Swift book?”
Who is this book for?
If you can answer “yes” to all of these:
Do you have access to a macOS or iPadOS device capable of running the latest public version of those operating systems?
Do you want to learn the principles of programming using the Swift programming language, so you can go further into the world of Swift?
Do you want to make apps one day, for iPhones or any other device in Apple’s ecosystem, or learn a vibrant open source language for web apps?
This book is for you.
Who should probably back away from this book?
If you can answer “yes” to any of these:
You’re already a powerful macOS, iOS, or Swift developer who wants a reference book.
You don’t want to be a programmer, and have no desire to learn to code.
You dislike pizza, or food, or drinks, or bad jokes.
This book is not for you.
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Note
[Note from marketing: this book is for anyone with a credit card.]
We know what your brain is thinking
Your brain craves novelty. It’s always searching, scanning, waiting for something unusual. It was built that way, and it helps you stay alive.
So what does your brain do with all the routine, ordinary, normal things you encounter? Everything it can to stop them from interfering with the brain’s real job—recording things that matter. It doesn’t bother saving the boring things; they never make it past the “this is obviously not important” filter.
How does your brain know what’s important? Suppose you’re out for a day hike and a tiger jumps in front of you. What happens inside your head and body?
Neurons fire. Emotions crank up. Chemicals surge.
And that’s how your brain knows...
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This must be important! Don’t forget it!
But imagine you’re at home, or in a library. It’s a safe, warm, tiger-free zone. You’re studying. Getting ready for an exam. Or trying to learn some tough technical topic your boss thinks will take a week, 10 days at the most.
Just one problem. Your brain’s trying to do you a big favor. It’s trying to make sure that this obviously non-important content doesn’t clutter up scarce resources. Resources that are better spent storing the really big things. Like tigers. Like the danger of fire. Like how you should never have posted those “party” photos on your Facebook page. And there’s no simple way to tell your brain, “Hey brain, thank you very much, but no matter how dull this book is, and how little I’m registering on the emotional Richter scale right now, I really do want you to keep this stuff around.”
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Metacognition: thinking about thinking
If you really want to learn, and you want to learn more quickly and more deeply, pay attention to how you pay attention. Think about how you think. Learn how you learn.
Most of us did not take courses on metacognition or learning theory when we were growing up. We were expected to learn, but rarely taught to learn.
But we assume that if you’re holding this book, you really want to learn how to program with Swift. And you probably don’t want to spend a lot of time on it. If you want to use what you read in this book, you need to remember what you read. And for that, you’ve got to understand it. To get the most from this book, or any book or learning experience, take responsibility for your brain. Your brain on this content.
The trick is to get your brain to see the new material you’re learning as Really Important. Crucial to your well-being. As important as a tiger. Otherwise, you’re in for a constant battle, with your brain doing its best to keep the new content from sticking.
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So just how DO you get your brain to treat Swift like it was a hungry tiger?
There’s the slow, tedious way, or the faster, more effective way. The slow way is about sheer repetition. You obviously know that you are able to learn and remember even the dullest of topics if you keep pounding the same thing into your brain. With enough repetition, your brain says, “This doesn’t feel important, but they keep looking at the same thing over and over and over, so I suppose it must be.”
The faster way is to do anything that increases brain activity, especially different types of brain activity. The things on the previous page are a big part of the solution, and they’re all things that have been proven to help your brain work in your favor. For example, studies show that putting words within the pictures they describe (as opposed to somewhere else on the page, like a caption or in the body text) causes your brain to try to make sense of how the words and picture relate, and this causes more neurons to fire. More neurons firing = more chances for your brain to get that this is something worth paying attention to, and possibly recording.
A conversational style helps because people tend to pay more attention when they perceive that they’re in a conversation, since they’re expected to follow along and hold up their end. The amazing thing is, your brain doesn’t necessarily care that the “conversation” is between you and a book! On the other hand, if the writing style is formal and dry, your brain perceives it the same way you experience being lectured to while sitting in a roomful of passive attendees. No need to stay awake.
But pictures and conversational style are just the beginning…
Here’s what WE did
We used visuals, because your brain is tuned for visuals, not text. As far as your brain’s concerned, a visual really is worth a thousand words. And when text and visuals work together, we embedded the text in the visuals because your brain works more effectively when the text is within the thing the text refers to, as opposed to in a caption or buried in a paragraph somewhere.
We used redundancy, saying the same thing in different ways and with different media types, and multiple senses, to increase the chance that the content gets coded into more than one area of your brain.
We used concepts and visuals in unexpected ways because your brain is tuned for novelty, and we used visuals and ideas with at least some emotional content, because your brain is tuned to pay attention to the biochemistry of emotions. That which causes you to feel something is more likely to be remembered, even if that feeling is nothing more than a little humor, surprise, or interest.
We used a personalized, conversational style, because your brain is tuned to pay more attention when it believes you’re in a conversation than if it thinks you’re passively listening to a presentation. Your brain does this even when you’re reading.
We included more than 80 activities, because your brain is tuned to learn and remember more when you do things than when you read about things. And we made the exercises challenging yet doable, because that’s what most people prefer.
We used multiple learning styles, because you might prefer step-by-step procedures, while someone else wants to understand the big picture first, and someone else just wants to see an example. But regardless of your own learning preference, everyone benefits from seeing the same content represented in multiple ways.
We include content for both sides of your brain, because the more of your brain you engage, the more likely you are to learn and remember, and the longer you can stay focused. Since working one side of the brain often means giving the other side a chance to rest, you can be more productive at learning for a longer period of time.
And we included stories and exercises that present more than one point of view, because your brain is tuned to learn more deeply when it’s forced to make evaluations and judgments.
We included challenges, with exercises, and we asked questions that don’t always have a straight answer, because your brain is tuned to learn and remember when it has to work at something. Think about it—you can’t get your body in shape just by watching people at the gym. But we did our best to make sure that when you’re working hard, it’s on the right things. That you’re not spending one extra dendrite processing a hard-to-understand example, or parsing difficult, jargon-laden, or overly terse text.
We used people. In stories, examples, visuals, etc., because, well, because you’re a person. And your brain pays more attention to people than it does to things.
Here’s what YOU can do to bend your brain into submission
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Note
Cut this out and stick it on your refrigerator.
So, we did our part. The rest is up to you. These tips are a starting point; listen to your brain and figure out what works for you and what doesn’t. Try new things.
Slow down. The more you understand, the less you have to memorize.
Don’t just read. Stop and think. When the book asks you a question, don’t just skip to the answer. Imagine that someone really is asking the question. The more deeply you force your brain to think, the better chance you have of learning and remembering.
Do the exercises. Write your own notes.
We put them in, but if we did them for you, that would be like having someone else do your workouts for you. And don’t just look at the exercises. Use a pencil. There’s plenty of evidence that physical activity while learning can increase the learning.
Read the “There are no Dumb Questions.”
That means all of them. They’re not optional sidebars, they’re part of the core content! Don’t skip them.
Make this the last thing you read before bed. Or at least the last challenging thing.
Part of the learning (especially the transfer to long-term memory) happens after you put the book down. Your brain needs time on its own, to do more processing. If you put in something new during that processing time, some of what you just learned will be lost.
Talk about it. Out loud.
Speaking activates a different part of the brain. If you’re trying to understand something, or increase your chance of remembering it later, say it out loud. Better still, try to explain it out loud to someone else. You’ll learn more quickly, and you might uncover ideas you hadn’t known were there when you were reading about it.
Drink water. Lots of it.
Your brain works best in a nice bath of fluid. Dehydration (which can happen before you ever feel thirsty) decreases cognitive function.
Listen to your brain.
Pay attention to whether your brain is getting overloaded. If you find yourself starting to skim the surface or forget what you just read, it’s time for a break. Once you go past a certain point, you won’t learn faster by trying to shove more in, and you might even hurt the process.
Feel something.
Your brain needs to know that this matters. Get involved with the stories. Make up your own captions for the photos. Groaning over a bad joke is still better than feeling nothing at all.
Write a lot of code!
There’s only one way to learn to program: writing a lot of code. And that’s what you’re going to do throughout this book. Coding is a skill, and the only way to get good at it is to practice. We’re going to give you a lot of practice: every chapter has exercises that pose a problem for you to solve. Don’t just skip over them—a lot of the learning happens when you solve the exercises. We included a solution to each exercise—don’t be afraid to peek at the solution if you get stuck! (It’s easy to get snagged on something small.) But try to solve the problem before you look at the solution. And definitely get it working before you move on to the next part of the book.
Read me
This is a learning experience, not a reference book. We deliberately stripped out everything that might get in the way of learning whatever it is we’re working on at that point in the book. And the first time through, you need to begin at the beginning, because the book makes assumptions about what you’ve already seen and learned.
We begin by teaching the concepts of Swift, bit by bit, and only bring it together once the foundations are in place.
You might want to write apps, but you can’t write apps for iPhones unless you know how variables and constants (and a whole lot more) work. So, we start with the basics before we get to the whole lot more. You’ll thank us later.
We don’t exhaustively cover everything.
There’s a lot of Swift to learn, and there are a lot of other good books out there (some of them even by us!) that cover Swift for readers with varying levels of expertise. There’s no point in this book discussing every facet of Swift. We cover the bits you need to know to get started and feel confident.
We pick the best bits to learn.
There are a lot of ways you can make a UI with Swift, from AppKit to UIKit to SwiftUI. We chose to teach a bit of SwiftUI in this book, and not cover the others. But because you’ll read about all the building blocks in this book, if you want to go and learn AppKit later, you’ll find it much easier.
The activities are NOT optional.
The exercises and activities are not add-ons; they’re part of the core content of the book. Some of them are to help with memory, some are for understanding, and some will help you apply what you’ve learned. Don’t skip the exercises. The crossword puzzles are the only thing you don’t have to do, but they’re good for giving your brain a chance to think about the words and terms you’ve been learning in a different context.
The redundancy is intentional and important.
One distinct difference in a Head First book is that we want you to really get it. And we want you to finish the book remembering what you’ve learned. Most reference books don’t have retention and recall as a goal, but this book is about learning, so you’ll see some of the same concepts come up more than once.
The examples are as lean as possible.
Our readers tell us that it’s frustrating to wade through 200 lines of an example looking for the 2 lines they need to understand. Most examples in this book are shown within the smallest possible context, so that the part you’re trying to learn is clear and simple. Don’t expect all of the examples to be robust, or even complete—they are written specifically for learning, and aren’t always fully functional.
We’ve placed a lot of the code on the web, so you can copy and paste it into Playgrounds and Xcode as you go. You’ll find the code at https://secretlab.com.au/books/head-first-swift.
The Brain Power exercises don’t have answers.
For some of them, there is no right answer, and for others, part of the learning experience is for you to decide if and when your answers are right. In some of the Brain Power exercises, you will find hints to point you in the right direction.
The technical review team
Technical Reviewers:
Huge thanks to the folks that helped us get the technology perfect for this book. They all spent a lot of time checking it over, and making sure it was good, and telling us off for doing something silly. We didn’t always take your comments literally, but they always drove us to make a better book.
Extra special thanks to Tim Nugent, Nik Saers, and Ishmael Shabazz.
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Acknowledgments
Our editor:
We literally couldn’t have written this book without Michele Cronin’s support, and we’d write something worthy of her and put it here if it were possible to do such a thing. We’ve written a lot of books over the years, and this one was probably the hardest, and had the longest process. We went through several editors before we found Michele (and they were all amazing), but when we found Michele this book started forming properly. She’s been supportive, and funny, and we’ve had some fantastic chats during our many, many meetings. We’re excited to be working with you on other things. Again: couldn’t have done this without you.
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The O’Reilly team:
Massive and sincere thanks to Christopher Faucher, the production editor on this book, without whom this book would not have cleanly come together. We’re really sorry we’re so terrible at InDesign.
Likewise, thanks to Kristen Brown for making sure everything was polished and Rachel Head for your fantastic copyedit (as usual) and support.
Thanks also to Zan McQuade, for not only being incredibly interesting and fun at all our meetings, but putting up with us complaining about InDesign, Apple, and everything in between.
Similarly, huge thanks to our friend and (one of our) original O’Reilly editors: Rachel Roumeliotis. We miss seeing you at conferences every few months, and we hope that starts happening again when this whole *gestures broadly* thing is over.
Thanks also to one of our original long-standing editors, Brian MacDonald, as well as the person who got us into writing books, Neal Goldstein.
We’re also really sorry for always using Australian English, mate.
Thanks to everyone at O’Reilly Media, broadly. They are literally the best. There is no team like them, and every new person at O’Reilly that we get to work with has been a pleasure to work with, the best at their job, and just an all-round fascinating person. They’re amazing.
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