Windows 8 introduces significant changes to the operating system's graphical user interface and platform; such as a new interface design incorporating a new design language used by other Microsoft products, a new Start screen to replace the Start menu used by previous versions of Windows, a new online store that can be used to obtain new applications, along with a new platform for apps that can provide what developers described as a "fast and fluid" experience with emphasis on touchscreen input.^[2] Additional security features were also added to the operating system, such as a built-in antivirus program and a secure boot feature on systems with UEFI firmware. Secure boot requires the operating system to be digitally signed to protect malware from infecting the boot process. The implementation of this feature has sparked controversy among supporters of free software. Windows 8 also introduces an edition of the operating system designed to run on devices that utilize the ARM architecture, known as Windows RT.

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