Microsoft Visual Studio 2012 LightSwitch is a rapid application development tool for creating data centric Silverlight and HTML applications.
LightSwitch is a designer-based addition to Visual Studio 2012 to assist in working with data-centric services and applications. When working with a LightSwitch project, the Visual Studio IDE changes to a development environment with only three main editors (in so-called “Logical mode”): the Entity Designer, the Query Designer and the Screen Designer. These editors focus on getting results quickly by being extremely intuitive, fast and easy to use. This adds some obvious benefits to the life of a LightSwitch developer:
First, it hides the plumbing (the repetitive code that’s typically associated with the development of these information systems). Easy-to-use editors mean fast development, fast development means productive developers and productive developers mean more value to the business. Or, as Scott Hanselman would say, “The way that you scale something really large, is that you do as little as possible, as much as you can. In fact, the less you do, the more of it you can do” (see Scott Hanselman's Personal Productivity Tips).
Second, and perhaps most important, nontechnical people, ranging from functional analysts to small business owners to Microsoft Access or Microsoft Excel “developers”—often referred to as citizen developers—who know the business inside out, can step in and help develop the application or even develop it entirely. The editors hide technological choices from those who prefer to avoid them and silently guide the application designer to apply best practices, such as encapsulating the domain logic in reusable domain models, keeping the UI responsive by executing business logic on a thread other than the UI thread, or applying the Model-View-ViewModel (MVVM) development pattern in the clients.
Finally, these editors actually don’t edit classes directly. Instead, they operate on XML files that contain metadata (LightSwitch Markup Language), which is then used by custom MSBuild tasks to generate code during compilation. This effectively frees the investment made in business logic from any technological choices. For example, a LightSwitch project that was made in version 1.0 would use WCF RIA Services for all communication between client and server, whereas that same project now compiles to use an Open Data Protocol (OData) service instead (more on OData later). This is about as adaptive to the ever-changing IT landscape as an application can get.
Source: Shape Up Your Data with Visual Studio LightSwitch 2012
