Microsoft Windows Server 2008 is the most advanced Windows Server operating system yet, designed to power the next-generation of networks, applications, and Web services. You can develop, deliver, and manage rich user experiences and applications, provide a secure network infrastructure, and increase technological efficiency and value within your organization.
Windows Server 2008 builds on the success and strengths of its Windows Server predecessors while delivering valuable new functionality and powerful improvements to the base operating system. New Web tools, virtualization technologies, security enhancements, and management utilities help save time, reduce costs, and provide a solid foundation for your information technology (IT) infrastructure.
Windows Server 2008 is built from the same code base as Windows Vista; therefore, it shares much of the same architecture and functionality. Since the code base is common, it automatically comes with most of the technical, security, management and administrative features new to Windows Vista such as the rewritten networking stack (native IPv6, native wireless, speed and security improvements
There are many version of Server 2008 versions. Datacenter, enterprise, standarad and windows server 2008 R2 .. , Windows server 2008 datacenter , windows 2008 enterprise and windows 2008 standard full version available here. Last stable version of windows 2008 family is Windows 2008 server R2. This also you can free download from this windows server 2008 free download page.