As PCs decline, Microsoft bets its future on the cloud

In a world where there's a smartphone app for everything, one company - Amazon.com Inc - has long been the host for an outsized share of online software and computing services.

Microsoft CEO Satya Nadella wants to change that.

Nadella has poured billions of dollars into building new data centers around the world, hoping to position Microsoft as the leading alternative to Amazon in selling online computing power - -housed in remote centers or "clouds" - to internet startups and big corporations, as well as consumers.