Get Going with Angular

On September 18, 2014, Google pushed the first public commit to the repository that now contains Angular. A few weeks later, at ng-europe, Igor, and Tobias, from the core team, gave a short overview of what were the expected features of the new framework. The vision at that time was far from final; however, one thing was certain: Angular would be an entirely different framework compared to AngularJS.

This announcement brought a lot of questions and controversies. The reasons behind the drastic changes were quite clear: AngularJS was no longer able to take full advantage of the evolved web and the requirements of large-scale JavaScript applications needed to be completely satisfied. A new framework would let Angular developers capitalize on developments in web technology in simpler, more performant, and productive ways. Yet, people were concerned. One of the biggest nightmares with backward incompatibility for developers is the migration of their current code bases to the new version of the third-party software they use. In Angular's case, after that first announcement, migration looked daunting, even impossible. Later, at ng-conf 2015 and ng-vegas 2015, different migration strategies were introduced. The Angular community came together and shared additional ideas, anticipating the benefits of the new version of the framework, while preserving the things learned from AngularJS.

This book is a part of that project. Making the upgrade to Angular is now smooth and is worth it. The main drivers behind the drastic changes in Angular 2 and its lack of backward compatibility are the evolution of the web and the lessons learned from the usage of AngularJS in the wild. This book will help you learn the new framework by making you understand how we got here and why Angular's new features make intuitive sense for the modern web in building high-performance, scalable, single-page applications.

Some of the topics that we will discuss in this chapter are as follows:

• Using TypeScript and understanding how it extends JavaScript
• Building the user interface of Angular applications with a component-based architecture
• Using Angular's dependency injection mechanism and delegating the business logic to services
• Exploring Angular's router and forms module in depth
• Looking at the Ahead-of-Time compilation for building lightning fast applications