Windows Azure[2] is a Microsoft cloud computing platform used to build, host and scale web applications through Microsoft data centers. Windows Azure is classified as platform as a service and forms part of Microsoft's cloud computing strategy, along with its software as a service offering, Microsoft Online Services. The platform consists of various on-demand services hosted in Microsoft data centers and commoditized through three product brands: Windows Azure[2] (an operating system providing scalable compute and storage facilities), SQL Azure (a cloud-based, scale-out version of SQL Server), and Windows Azure AppFabric (a collection of services supporting applications both in the cloud and on premise).

Windows Azure has three core component :
Compute which provides a computation environment with Web Role, Worker Role, and VM Role.
- Storage which focuses on providing scalable storage (Blobs, non-relational Tables, and Queues) for large-scale needs (Relational Database functionality is offered through SQL Azure, which is a scalable version of SQL Server that runs on the Azure platform).
- Fabric which uses high-speed connections and switches to interconnect nodes consisting of several servers. Fabric resources, applications, and services running are managed by the Windows Azure Fabric Controller service. It acts as the kernel of the Windows Azure distributed cloud operating system, providing scheduling, resource allocation, device management, and fault tolerance for the nodes in the Fabric. It also provides high-level application models for intelligently managing the complete application lifecycle, including deployment, health monitoring, upgrades, and de-activation

The Windows Azure Platform provides an API built on REST, HTTP, and XML that allows a developer to interact with the services provided by Windows Azure. Microsoft also provides a client-side managed class library which encapsulates the functions of interacting with the services. It also integrates with Microsoft Visual Studio so that it can be used as the IDE to develop and publish Azure-hosted applications.