In the past five years, due to the evolution of Web browsers, focus has shifted from Desktop applications to Web applications. More companies are realizing that the web is a perfect platform to create tools to save people time and money by providing quick and easy access to their service. Whether it is ordering pizza or Internet banking, web applications are fast becoming the platform of choice for the modern business. These modern companies know that, if they were to build an application for a specific platform, like the iOS or Windows operating systems, they would be inherently restricting their audience, as each operating system has its own percentage of the total user base. They've realized that in order to reach everyone, they need a ubiquitous platform that exists in all operating systems. This platform is the Web. So, if everyone with Internet access has a browser, then by targeting the browser as our platform, our potential user base becomes everyone on the Internet.

The Google product line is a prime example of a business successfully utilizing the browser platform. This product line includes: Google Search, YouTube, Gmail, Google Drive, Google Docs, Google Calendar, and Google Maps. However, providing a rich user experience comes with a cost. These applications are tremendously more complex than a traditional website made with jQuery animated menus.

Complex JavaScript Web Applications require considerable design and planning. It is quite common for the client-side (or browser) JavaScript code to be more complicated than the server-side code. With this in mind, we need to ensure our code base is manageable and maintainable. The key to code manageability and maintainability is to logically structure our project and to keep our code DRY. Structuring includes the file and directory structure as well as the code structure (that is HTML, CSS, and JavaScript structure). Maintaining a logical directory structure provides predefined locations for all types of files. This allows us to always know where to put our code, which is very important for rapid development. DRY stands for Don't Repeat Yourself (http://gswg.io#dry). Hence, to keep your code DRY is to write code where there is little or no repetition and we embrace the idea of a "single source of truth". Similarly, we want to avoid repetition surrounding our build process. As we'll see throughout this book, Grunt is a great tool for achieving these goals.