Microsoft chief executive Steve Ballmer has used this year's CeBIT show in Hanover to highlight what he calls the "fifth computing revolution".

"The last time I spoke here was in 2002. In that speech I mentioned that I had been at Microsoft for 22 years and lived through three computing revolutions," he said.

"Now, six years later, I have been at Microsoft for 28 years and I can say that I have lived through four revolutions."

Ballmer broke down these four "computing revolutions" as:

• The personal computer becoming an affordable mainstream product which put computing power in the hands of individuals for the first time
• The emergence of the Graphical User Interface making it easier for users to take advantage of the power of computing
• The rise of the internet when email became an everyday communications tool and information became dramatically easier to find and share
• The rise of web 2.0 in which the internet evolved from static pages and information to become a platform for services, and for publishing and sharing information

Ballmer went on to describe his vision of the fifth revolution in which computing will be driven by personal empowerment, social interaction and global issues.

"In my 28 years at Microsoft I have lived through four computing revolutions but they have simply been a foundation for the much more profound changes to come in the next revolution," he said.

Ballmer went on to lay out the key trends he believes are shaping this impending revolution.

"The first is the hardware advances that are putting more and more processing power into smaller and smaller devices," he said.

"The second is significantly expanded storage on PCs and devices of all sizes, and in massive data centres around the world. A third trend is the availability of wireless broadband networks everywhere."

Ballmer also highlighted the growing use of natural user interfaces, both in terms of displays that are driven by touch and gestures as well as the advancement of speech recognition systems.

"During the fifth revolution, expanded processing, huge amounts of storage, ubiquitous broadband, natural user interfaces and screens everywhere will help us address global warming, and improve healthcare and education for billions of people around the world," he explained.

"It will transform human social interaction and make computers more useful and more personal. Access to information, communications and computing capabilities will be seamless and natural."

Describing his vision of personal empowerment in the fifth revolution, Ballmer said that, although we now use computing in more and more places, it is still too complicated and disconnected.

Managing this increasing content across multiple devices and sources involves a high degree of difficulty, according to Ballmer.

"During the fifth revolution this will change. Soon, you will be able to call up any document, photo or media file instantly on whatever device is at hand," he said.

"You will not need to know where your information is stored. It will not matter what device you are using. You will just log on, click and instantly get access."