You can download the ISO files for WIndows 8.1 Preview from this page.
Windows 8 was launched in several editions and you can buy the one that suits your needs best. Windows 8 can be purchased via this link, and upgrading to the Pro license requires buying Windows 8 Pro Pack. Windows 8 Pro features additional protection due to BitLocker and the PC can host a Remote Desktop Connection; it can be bought via this link. Students who are currently running a genuine copy of XP, Vista or 7 can upgrade to Windows 8 for a discounted price.
Windows 8 was launched in October 2012, and it is the first operating system developed by Microsoft that aims to bring the same user experience on desktops, laptops, tablets and mobile phones (via Windows Phone 8).
While its user interface might not seem too different from the one of Windows 7, it still comes with some modifications, including the removal of the Aero transparency and of the rounded corners, as well as implementation of the ribbon-style look for Windows Explorer.
One of the greatest changes is related to the Start Screen which replaces the Start Menu altogether, as the installed applications can be accessed using their dedicated tiles. The Modern UI (initially called the Metro UI) also includes a so-called Charms Bar which displays a vertical toolbar to the right side of the screen, allowing people to share data, open the Control Panel and access the power options.
In addition to the traditional way of downloading and installing programs, Windows 8 users can also rely on the Windows Store, an online resource of numerous apps compatible with the OS, similar to the way other mobile marketplaces function – when using this online platform, users are no longer required to download the app first, as it gets automatically installed.
Another innovation of Windows 8 is its faster boot mode, based on a technology called UEFI (Unified Extensible Firmware Interface) and which can only be activated on computers with specialized hardware. UEFI is basically meant as a replacement for the old BIOS firmware interface and it helps PC open much faster than before.
In addition to USB 3.0 support, integration with Windows Live accounts and synchronization between all PCs belonging to the same account, along with the Windows To Go feature, Windows 8 has a lot more to offer to its users who are willing to give it a try.

Limitations:
· 90 days trial

What's New in This Release:
· It delivers new apps powered by Bing, including ones for Travel, News and Sports
· Improvements to Mail, Photos and People apps since Consumer Preview;
· Increased personalization options for the Start screen;
· Improved multi-monitor support;
· Refinements to the way people find and download apps through the Windows Store;
· New Family Safety features and enriched privacy and security controls when browsing online, including Do Not Track capabilities being turned on by default with Internet Explorer 10;
· Enriched support for touch with Internet Explorer 10, including a new capability with Release Preview called “flip ahead” that allows users the option to flip between pages with the swipe of a finger, as well as a touch-friendly Adobe Flash Player now fully integrated into IE10, allowing customers to enjoy all the security and power benefits of browsing, even on Flash-powered sites;
· IE10 is also the first browser to enable Do Not Track “on” by default, giving customers more choice and c...