Super-fast and great-looking, Ubuntu is a secure, intuitive operating system that powers desktops, servers, netbooks and laptops. Ubuntu is, and always will be, absolutely free. I personally remcomend this for a new user. It dose not mean it would not be perfect for advance user. It has every feature what an advance user want. And it can be installed under microsoft OS, Like other programs. Even it has the capability to run without modifying your hard drive. That mean you can run it Live from the installation disk(CD).
Just look at the some feature:
OpenOffice.org is fully compatible with Microsoft Office and has everything you need to create professional documents, spreadsheets and presentations. OpenOffice.org is easy to use, packed with the features you need and completely free.
Ubuntu Software Centre
The Ubuntu Software Centre gives you instant access to thousands of open-source and carefully selected free applications. And now you can buy apps too. Browse software in categories including: education, games, sound and video, graphics, programming and office. All the applications are easy to find, easy to install and easy to buy.
Ubuntu includes Mozilla Firefox – for fast, safe web browsing. You can also choose alternative browsers including Google Chromium from the Ubuntu Software Centre.
Get chatting with Empathy. Quickly integrate your chat accounts from Yahoo, Gmail, MSN, Jabber, AOL, QQ and many more. Evolution Mail provides easy, intuitive email.
Ubuntu One Music Store
New in 10.10. Ubuntu's music player includes an integrated store, so you can buy and download new tracks with just a few clicks. And thanks to Ubuntu One's file-syncing magic you can stream your music uninterrupted to your Android device or iPhone.
Ubuntu is chock full of apps to help you manage, fix and share your photos with the world, whatever gadget you use to take them. Support for cameras and phones is legendary and all without drivers. And Shotwell allows you to manage and share your pictures easily - on all the most popular photo and social network sites.
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