VMware allows you to run 'virtual machines' inside a Linux host. It is not an emulator. It provides a virtual computer within the host which can boot whichever OS you decide to put on the filesystem image that is used as a harddrive. It will run DOS 6.22, Win 3.1, Win9x, WinNT/2000/XP/2003, Linux, Novell, and more. The only main requirement is a 400 MHz or better machine, along with lots of RAM (128M minimum, 256M recommended). License: Other/Proprietary License with Free Trial Changes:
Several security vulnerabilities, reported as CORE-2007-0930, and Foundstone CODE-BUG-H-001, were fixed. Libpng was updated to remove various security vulnerabilities. OpenSSL was updated to solve its security vulnerabilities reported as CVE-2006-2940, CVE-2006-2937, and CVE-2006-4343. Anonymous console access to the guest by means of the VIX API was disabled. Several other bugs were fixed, such as USB device and iPhone handling, Windows guest shared folder access and offline files, X.org 1.3 detection, and many more.

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