Features new to Windows Vista Windows Vista, Internet Explorer operates in a special "Protected Mode", which runs the browser in a security sandbox that has no access to the rest of the operating system or file system, except the "Temporary Internet Files" folder. This feature aims to mitigate problems whereby newly discovered flaws in the browser (or in ActiveX controls hosted inside it) allowed hackers to subversively install software on the user's computer (typically spyware). Internet Explorer 7 in Windows Vista also exclusively supports Advanced Encryption Standard (AES) key lengths up to 256 bits outlined in RFC 3268 and certificate revocation checking using Online Certificate
Operating system systems that have fixed deadlines use a real-time operating system such as VxWorks, PikeOS, eCos, QNX, MontaVista Linux and RTLinux. Windows CE is a real-time operating system that shares similar APIs to desktop Windows but shares none of desktop Windows' codebase. Symbian OS also has an RTOS kernel (EKA2) starting with version 8.0b. Some embedded systems use operating systems such as Palm OS, BSD, and Linux, although such operating systems do not support real-time computing. Operating system development is one of the most complicated activities in which a computing hobbyist may engage. A hobby operating system may be classified as