FreeBSD® is an advanced operating system for x86 compatible (including Pentium® and Athlon™), amd64 compatible (including Opteron™, Athlon™64, and EM64T), UltraSPARC®, IA-64, PC-98 and ARM architectures. It is derived from BSD, the version of UNIX® developed at the University of California, Berkeley. It is developed and maintained by a large team of individuals. Additional platforms are in various stages of development.

The FreeBSD developers are as concerned about security as they are about performance and stability. FreeBSD includes kernel support for stateful IP firewalling, as well as other services, such as IP proxy gateways, access control lists, mandatory access control, jail-based virtual hosting, and cryptographically protected storage. These features can be used to support highly secure hosting of mutually untrusting customers or consumers, the strong partitioning of network segments, and the construction of secure pipelines for information scrubbing and information flow control.

FreeBSD also includes support for encryption software, secure shells, Kerberos authentication, "virtual servers" created using jails, chroot-ing services to restrict application access to the file system, Secure RPC facilities, and access lists for services that support TCP wrappers.



Cutting edge features
FreeBSD offers advanced networking, performance, security and compatibility features today which are still missing in other operating systems, even some of the best commercial ones.

Powerful Internet solutions
FreeBSD makes an ideal Internet or Intranet server. It provides robust network services under the heaviest loads and uses memory efficiently to maintain good response times for thousands of simultaneous user processes.

Run a huge number of applications
The quality of FreeBSD combined with today's low-cost, high-speed PC hardware makes FreeBSD a very economical alternative to commercial UNIX® workstations. It is well-suited for a great number of both desktop and server applications.

Easy to install
FreeBSD can be installed from a variety of media including CD-ROM, DVD-ROM, floppy disk, magnetic tape, an MS-DOS® partition, or if you have a network connection, you can install it directly over anonymous FTP or NFS. All you need are these directions.

FreeBSD is free
While you might expect an operating system with these features to sell for a high price, FreeBSD is available free of charge and comes with full source code. If you would like to purchase or download a copy to try out, more information is available.

Contributing to FreeBSD
It is easy to contribute to FreeBSD. All you need to do is find a part of FreeBSD which you think could be improved and make those changes (carefully and cleanly) and submit that back to the Project by means of send-pr or a committer, if you know one. This could be anything from documentation to artwork to source code. See the Contributing to FreeBSD article for more information.
Even if you are not a programmer, there are other ways to contribute to FreeBSD. The FreeBSD Foundation is a non-profit organization for which direct contributions are fully tax deductible. Please contact board@FreeBSDFoundation.org for more information or write to: The FreeBSD Foundation, P.O. Box 20247, Boulder, CO 80308, USA.

Here are some examples of the environments in which FreeBSD is used:
* Internet services. Many Internet Service Providers (ISPs) find FreeBSD ideal, running WWW, Usenet news, FTP, Email, and other services. Ready-to-run software like the Apache web server or the ProFTPD FTP server make it easy to set up a business or community-centered ISP. Of course, with FreeBSD's unbeatable networking, your users will enjoy high speed, reliable services.
* X Window workstation. From an inexpensive X terminal to an advanced X display, FreeBSD works quite well. Free X software (X.Org™) comes with the system. nVidia offers native drivers for their high-performance graphics hardware, and the industry standard Motif® and OpenGL® libraries are supported. Both the KDE and GNOME desktop environments enjoy full support and provide office suite functionality, with further good functionality available in the OpenOffice.Org and TextMaker products.
* Networking. From packet filtering to routing to name service, FreeBSD can turn any PC into a Internet firewall, email host, print server, PC/NFS server, and more.
* Software development. A suite of development tools comes with FreeBSD, including the GNU C/C++ compiler and debugger. Java™ and Tcl/Tk development are also possible for example, and more esoteric programming languages like Icon work just fine, too. And FreeBSD's shared libraries have always been easy to make and use. You can also choose from a wide range of popular and powerful editors, such as XEmacs and Vim.
* Net surfing. A real UNIX workstation makes a great Internet surfboard. FreeBSD versions of Firefox and Opera are available for serious web users. Surf the web, publish your own web pages, read Usenet news, and send and receive email with a FreeBSD system on your desktop.
* Education and research. FreeBSD makes an excellent research platform because it includes complete source code. Students and researchers of operating systems or other computer science fields can benefit greatly from such an open and well-documented system.
* And much more. Accounting, action games, MIS databases, scientific visualization, video conferencing, Internet relay chat (IRC), home automation, multiuser dungeons, bulletin board systems, image scanning, and more are all real uses for FreeBSD today.


SO: Windows Unix

Licenza: Freeware

	http://www.freebsd.org/

- (LINK! - X86)

	ftp://ftp15.us.freebsd.org/pub/FreeBSD/ISO-IMAGES-i386/8.0/

- (LINK! - X64)

	ftp://ftp.freebsd.org/pub/FreeBSD/releases/amd64/ISO-IMAGES/8.0/