As the world moves into "an era of solutions that are experienced by users across PCs, phones and the web" and delivered from remote data centers, Ozzie said, Windows Azure and SQL Azure will meet those needs because they were built "specifically for this era of cloud computing."

'Three Screens and a Cloud'

Ozzie described Microsoft's vision of the future of software delivery as "three screens and a cloud," with the screens being PCs, phones and TVs connected by cloud-based services.

The company intends for Azure to provide a platform that remotely handles the complexity of development and deployment environments, with access to virtually unlimited additional capacity quickly and on a pay-as-you-go basis.

Also unveiled was an online marketplace for the company's partners to sell their applications. Called Microsoft Pinpoint, one of its products will be the company's own information service, code-named Dallas, that allows developers to gain access to data sets and content on any platform. Dallas' offerings include content and data from the Associated Press, WaveMarket, the United Nations, NASA, infoUSA and others.

In Microsoft's vision, developers would use .NET Framework, Visual Studio tools and technologies, and such third-party tools as Eclipse. A customer 's applications could be located in private or public clouds and extended with cloud-based services, and resources quickly provisioned if needed.

Also introduced was Windows Server AppFabric, a set of integrated technologies for developing and managing IIS-based apps on either a server or in the cloud. AppFabric's hosting and caching technologies, combined with the Azure platforms' AppFabric Service Bus and AppFabric Access Control -- formerly .NET Services -- expand Windows Server and Azure into a common foundation for .NET apps.

OS 'Services in the Cloud'

Along with other software giants such as Amazon, Google and Salesforce, Microsoft sees cloud computing as a large part of computing's future, especially in the enterprise . But the company got its fingers burned on cloud computing recently when a subsidiary, appropriately called Danger, had to tell Sidekick customers that their cloud-based data was lost and then, bit by bit, announced restoration of the data.

Al Hilwa, program director at industry research firm IDC, noted that Microsoft needs to find ways "to transition some of their workload and technologies to the cloud side" as it continues to adapt to the world of mobile, cloud computing and web development.

The best way to think of Azure, he said, is "as a set of operating-system services in the cloud," which Microsoft is one of the few companies with the scope and resources to provide. Hilwa added that a key to the success of Azure is the extent to which it can bring existing applications to the cloud, so developers and businesses can leverage existing efforts as well as existing skills, such as experience with .NET.