Microsoft Corp and Hewlett-Packard Co announced a partnership on Wednesday to integrate their software and hardware offerings for companies looking to move their applications and data online, popularly known as cloud computing.

The world's biggest software maker and the world's No. 1 PC maker, which have cooperated in this area for some time, said they would invest $250 million over three years in marketing and supporting the new venture.

The two hope the combined effort will make it easier and more cost-effective for companies to buy and operate server systems, essentially combining Hewlett-Packard's hardware and Microsoft's software.

The cloud is a significant inflection point in how our customers will be building their next generation applications, said Bob Muglia, the head of Microsoft's server and tools business, in a telephone interview.

We (Microsoft and Hewlett-Packard) have decided to double down and commit to building the next generation architecture, said Muglia.

Cloud computing -- broadly the practice of storing information and running computer programs in remote data centers that are accessible over the Internet -- has long been expected to revolutionize business computing, but actual take-up has been gradual.

Microsoft launched its Azure cloud computing service earlier this month, giving customers the option of storing data in Microsoft's data centers and providing software developers a platform for creating cloud-based applications.

Rivals such as Amazon.com Inc and Salesforce.com Inc have been selling cloud-based services for some time.

(Reporting by Bill Rigby; Editing by Phil Berlowitz)