Windows is great, but after a while, it can get cluttered up with too many programs and become intolerably sluggish. Backing up your files and reinstalling it can help, but an alternative is to try the free Ubuntu operating system. Ubuntu isn't too demanding and can make even a lowly netbook seem sprightly compared with running Windows on it.

Ubuntu is one of many Linux distributions, but it's arguably the most polished, most compatible and best supported (around 20 million people use it on a daily basis). The latest version, discounting beta releases, is 11.10 Desktop Edition. This is a one-size-fits-all version which will run on anything from a humble netbook to a top-end desktop PC with multiple monitors.

See also: How to install Ubuntu using a USB flash drive

It's thanks to the new Unity interface which, just like Windows 8's new Metro interface, scales from low-resolution screens right up to the highest resolutions offered by PC monitors while retaining the same look. You can test drive Ubuntu from Windows at this website and choosing either the guided tour or to show yourself around.

Ubuntu looks a lot like Mac OS X as it has a status bar running across the top of the screen. A program dock appears on the left and scrolls when you hover your mouse cursor near the top or bottom. It comes with lots of software including the excellent LibreOffice - a Microsoft Office lookalike - a decent photo manager, Firefox, email client and more.

Crucially, there's the Ubuntu Software Centre where you can download thousands of free applications. These are all user rated, just like Apple and Google's respective app stores, so you can get an immediate idea of which are the best choices.

Another new feature is the Ubuntu One online backup service. You get 5GB of free storage for backups, music streaming and synching across multiple computers. You can still install and use your favourite applications, though, so if you're already a Dropbox user, that's no problem: simply install Dropbox from the Ubuntu Software Centre and use that instead.

If you tried Linux (or even Ubuntu itself) before but were put off by the confusing interface, difficult installation or lack of hardware support, it's well worth giving it another try now. Most popular hardware is supported, so you shouldn't have any problems such as your webcam or Wi-Fi not working.

We installed Ubuntu 11.10 on an Asus Eee PC 901 netbook for this article and found that even the keyboard shortcuts for volume and brightness worked first time. Drivers had been correctly installed for wired and wireless networking, plus Bluetooth. The experience was akin to installing Windows 7, so there's really no excuse for not giving it a go.

Of course, apart from the fact that Ubuntu is free, the main reason many people choose it is for its performance. The minimum requirements of 64MB RAM and 5GB hard disk space mean just about any computer should be able to run the operating system. It's best to stick to the recommended minimum of 512MB of RAM to avoid frustrations with performance, though.

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