As a developer of Microsoft technologies I alway think about what programming model and tools are provided by the platform. On Microsoft new operation system Windows 8 developer write two type of applications first one is Metro Style Apps and second one is Desktop Apps.
Metro Style Apps
Metro style apps are full screen apps tailored to your users' needs, tailored to the device they run on, tailored for touch interaction, and tailored to the Windows user interface.
Normal Windows applications that we are using in Windows 7 and Windows Vista like msn messanger,
MS Word etc.
Following diagram show the programming model and Tools for Windows 8
Figure 1: Windows 8 Platform and Tools