Nadella, 47, was addressing over 12,000 Microsoft partners, senior company executives, technology experts and analysts during the Microsoft Worldwide Partner Conference 2015 at the sprawling Orange County Convention Centre here in the US state of Florida.
Noting that Microsoft is focused on helping its customers achieve "greatness through digital technology," Nadella, who took over as the third CEO in the history of the tech giant in February last year, gave the audience a glimpse of the mission and "sense of purpose" driving the company going forward.
Listing the three "bold ambitions" for Microsoft, Nadella, said one ambition is personal computing, which is "the very core of our company."
"Windows 10 is going to usher in this new era of more personal computing. We couldn't be more excited, three weeks away from launch. It is not just the technology but what Windows means for this ecosystem is what is driving us," Nadella said in his keynote address at the conference.
He added that Windows 10 is going to run on everything from phones to tablets to surface hubs as well as to the HoloLens, Microsoft's first fully untethered, see-through holographic computer.

He said through Windows 10, there will be "one unifying platform, one unifying experience" and "that to me is the clear differentiator of what Winsdows stands for".
He said Windows 10 will enable users to interact with it in the "most natural way" and they will be able to speak to it touch it and use it seamlessly in their personal and professional lives.
"The natural interaction is going to be a unique capability of this one operating system. We will also lead the way in the management and security of windows devices," he said.
Highlighting the second ambition for the company, Nadella said it will be the reinvention of productivity and business process.
"Central to this ambition is the reinvention of even the category definition of business process and productivity. We don't think of these things as separate things anymore. We want to bring together everything that is related to core creation, communication, collaboration in business process and blend them together," he said.
The other ambition that the company is focused on is building an intelligent cloud.