Live Mesh connects devices and services online and offline
Microsoft has lifted the lid on a new web service called Live Mesh, designed to connect a multiplicity of devices and applications online.
The service is seen by many as a key plank in the company's vision for the future of the web.
Live Mesh is designed to blur the lines between running software and storing data on a desktop and "in the cloud".
Microsoft's Amit Mital said Live Mesh would "connect and bring devices together... to work in concert".
Live Mesh pits Microsoft against companies like Amazon, Google and Salesforce.com which are already offering different varieties of so-called software-as-a-service systems.
It comes as Microsoft is engaged in a bid to buy rival Yahoo and emphasises just how important the web has become to the firm.
"We may be seeing signs of a Microsoft that is newly focused," Jonathan Yarmis, a vice president and analyst at AMR Research, told Reuters news agency.
He added: "This is exciting because it has as much to do with who is doing it as what Microsoft is doing."
Microsoft has long been criticised for its unfocused efforts in the online space and for attempting to tie the use of Windows to the web.
While initially offered for Windows XP and Vista users, Microsoft has said Live Mesh will also be rolled out to Apple Macs and other platforms.
Mr Mital, general manager of Live Mesh, said: "Devices are how we interact in this new "web-connected" world and we use a variety of them, including PCs, laptops, media devices, phones, digital picture frames, game consoles, music players and the list grows at every CES.
Live Mesh is a web-based platform
"However, as we discover, adopt and use more of these digital devices, it becomes increasingly difficult to keep the people, information and applications we depend on in sync."
Microsoft says Live Mesh can be used to create an online network of devices, from your PC to your mobile phone.
Files and folders, such as documents, music and photos, on those devices can be synchronised online and accessed via a web browser.
Live Mesh is also designed to facilitate the sharing of media online between different users.
"This new software-plus-services platform enables PCs and other devices to 'come alive' by making them aware of each other through the internet," said Mr Mital.
"We aspire to bring together Windows, Windows Live, and Windows Mobile by creating seamless experiences that span these offerings," Ray Ozzie, Microsoft's chief software architect, wrote in a memo to staff this week.
Users will have 5GB of personal online storage and unlimited peer-to-peer data, for synchronising information between devices.