Info: Coded in C/C++ OSX is unix-like operating system developed by apple for their computers. I don't see anything mroe interesting about this OS because i've never had an MAC and i don't think ill have.
Info: Solaris is a Unix operating system originally developed by Sun Microsystems, now owned and developed by Oracle. Solaris is known for its scalability, especially on SPARC systems, and for originating many innovative features such as DTrace, ZFS and Time Slider. Solaris supports SPARC-based and x86-based workstations and servers from Oracle and other vendors, with efforts underway to port to additional platforms. Solaris is registered as compliant with the Single Unix Specification.
Info: FreeBSD is an advanced computer operating system used to power modern servers, desktops and embedded platforms. A large community has continually developed it for more than thirty years. Its advanced networking, security and storage features have made FreeBSD the platform of choice for many of the busiest web sites and most pervasive embedded networking and storage devices.
Info: PC-BSD is a user friendly desktop Operating System based on FreeBSD. Known widely for its stability and security in server environments, FreeBSD provides an excellent base on which to build a desktop operating system. PC-BSD uses a host of popular open source window managers and uses a custom-tailored application installer that puts popular applications in easy reach of users.
Info: OpenBSD is a Unix-like computer operating system descended from Berkeley Software Distribution (BSD), a Unix derivative developed at the University of California, Berkeley. The OpenBSD Project has produced portable versions of numerous subsystems, most notably PF, OpenSSH and OpenNTPD, which are very widely available as packages in other operating systems. The OpenBSD project produces a FREE, multi-platform based UNIX-like operating system. Our efforts emphasize portability, standardization, correctness, proactive security and integrated cryptography.
Info: NetBSD is a free, fast, secure, and highly portable Unix-like Open Source operating system. It is available for a wide range of platforms, from large-scale servers and powerful desktop systems to handheld and embedded devices. Its clean design and advanced features make it excellent for use in both production and research environments, and the source code is freely available under a business-friendly license. NetBSD is developed and supported by a large and vivid international community. Many applications are readily available through pkgsrc, the NetBSD Packages Collection.
Name: DragonFly BSD
Info: DragonFly belongs to the same class of operating systems as other BSD-derived systems and Linux. It is based on the same UNIX ideals and APIs and shares ancestor code with other BSD operating systems. DragonFly provides an opportunity for the BSD base to grow in an entirely different direction from the one taken in the FreeBSD, NetBSD, and OpenBSD series. DragonFly includes many useful features that differentiate it from other operating systems in the same class. The most prominent one is HAMMER, our modern high performance filesystem with built-in mirroring and historic access functionality.
Info: pfSense is a free, open source customized distribution of FreeBSD tailored for use as a firewall and router. In addition to being a powerful, flexible firewalling and routing platform, it includes a long list of related features and a package system allowing further expandability without adding bloat and potential security vulnerabilities to the base distribution. pfSense is a popular project with more than 1 million downloads since its inception, and proven in countless installations ranging from small home networks protecting a single computer to large corporations, universities and other organizations protecting thousands of network devices.
Info: Gentoo/DragonFlyBSD is a currently unofficial port to the DragonFlyBSD kernel. The project is developed by Robert Sebastian Gerus.
Sources: http://www.wikipedia.org and the official OS sites.