Microsoft

Needing little introduction, Microsoft, in addition to their many other abilities,  provide Server and Tools licensed products together with applications, tools, content, and services that are designed to make information technology professionals and developers more productive and efficient. Server and Tools offerings consist of server software licenses and client access licenses ("CAL") for Windows Server, Microsoft SQL Server, and other server products. They offer developer tools, training, certification, Microsoft Press, Premier and Professional product support services, and Microsoft Consulting Services.

www.microsoft.com