If you want to become an iOS developer, you have made an excellent choice with this book. Swift holds a significant position in the iOS industry because of the long list of features it serves. It is user-friendly, has great community support, and offers a greater extent of customization. As a result, we can observe a sharp increase in the market demand for developing Apple mobile applications, and with that, companies search for smart developers with the right skill set. Mastering Swift introduces Apple's excellent Swift standard library style and incorporates usage feedback across multiple Swift projects. However, it should be regarded as a living, changeable document and the basis upon which the programming language is implemented. Before going further into the details of the Swift programming language, the book briefly explains the basic information about the language. It is a high-level language created to develop multifaceted iOS applications that cater to diverse needs of different social and business domains. It is meant to develop high-end apps with multiple complexities. But since it is very close to Objective C, it is easy to code and understand. This feature also makes it incredibly friendly to beginners. Moreover, it is equally compatible with the iPhone, the iPad, Apple Watch, MacBook, and Apple TV, and it can be applied to develop equally efficient and scalable apps for them. This book in the Mastering series encircles all the essential aspects of Swift and explores why this programming language is the future for iOS app development. Different from other languages, it requires fewer lines to activate any feature. This paves the way for a shorter development cycle and saves a lot of precious resources. Further, as one of the most reliable iOS programming languages it supports dynamic libraries that indicate executable bits of code that you can link to an application. Because of such support, Swift apps can interoperate with the newest version of the language to make the app irreplaceable. Swift is a language that was not designed but deliberately made open source so as to invite community input, allowing the product to grow and to mature over the years. This could possibly be the most crucial aspect of Swift. As people become more aware of its potential to be used in servers, web frameworks were more willing to support the demand. Owing to its popularity and significance, its adoption rate in