For decades, the PC - or 'personal computer' - has been the hub of our digital lives. Heavy boxes of computer hardware sat in our living rooms, storing data, crunching numbers, and running applicationsAn official request for something. Also, 'applications', or 'programmes' are processes that work with stored information to produce the desired result. To watch a film on a computer, for example, you need an application to turn the raw data (stored as 1s and 0s) into a picture on your screen. like games, media players, and office programs.

Now, with the next wave of computer innovation, that's set to change. A new service just unveiled by tech-giants Apple will build on existing services from Google and Amazon to push our digital lives away from personal hardware and onto then intangible network known as 'the cloud.'

So what is this 'cloud' that's poised to make the PC obsolete? It's a hard question to answer. The cloud is everywhere. It has no physical form. It has no set boundaries. The old method of computing was built around individual machines. The cloud is a network that spans the globe.

The recent Apple announcement, for example, was for a service called iCloud. Users will be able to store data like documents, films, and music in folders that can be accessed from anywhere, on any Apple device. You could start watching a film on your Mac at home, then switch to an iPhone or iPad on the bus, then catch the final scene on a friend's computer somewhere else entirely.

Cloud services like this work by holding information online, using vast servers around the world to provide memory and processing power. And it's not just files that are moving online.

Increasingly, even quite complex applications can be run on the web, and accessed from any device which can open a browser window. With services like Google Docs, for example, you could carry out word processing tasks from a smartphone, a tablet computerTablet computers are somewhere between laptops and smartphones. The most famous example is the Apple iPad., or even a web-enabled TV.

Software and informationComputers have three key ingredients. Memory stores information in 1s and 0s. Software processes that information and allows users to work with it. Hardware is the physical machinery that allows software to run, and which allows users to control software. are moving online fast. Meanwhile, hardware is disappearing entirely. For example, gamers at this year's E3 convention have just been shown the second generation of games built for Microsoft's Kinect. Traditionally, games are controlled with physical joysticks and pads. Kinect allows players to navigate digital worlds using voice commands, gestures, and even eye movements.

So what does all this mean? The pattern that's emerging is one where technology begins to disappear. That doesn't mean it will stop existing - far from it - but each advance takes us closer to a world where there are no obvious technological steps between us and what we want to do.

If we want a certain movie or a particular document, we could summon it with a wave of a hand. Communicating with distant friends might become as simple as saying their names. To visitors from the past, that wouldn't look like technology - it would look like a superpower.