What Is Windows Server?

What Windows Server Is

Windows Server is Microsoft's operating system for servers. It shares its core code with desktop Windows but is built to host shared services, such as websites, databases, file storage and user logins, for many people or machines at once. It is sold as a separate product and licensed differently from the desktop version.

Like other server operating systems, Windows Server manages hardware, runs many services at the same time, handles networking and controls who can log in and what they can access. Microsoft offers several editions, mainly Standard and Datacenter, which differ in the virtualization rights they include. For the general concept, see what a server operating system does.

Common Roles: IIS, Active Directory and More

Windows Server is organized around roles and features that administrators install as needed. The ones most often seen in hosting are:

• Internet Information Services (IIS): Microsoft's web server, used to host websites and ASP.NET applications.
• Active Directory Domain Services: a central directory that manages user accounts, computers and access rights across a network.
• DNS and DHCP: name resolution and automatic IP address assignment for networks.
• Remote Desktop Services: graphical remote access and shared application sessions for many users.
• Hyper-V: virtualization for running several virtual machines on one physical server.

A server should carry only the roles it uses. Each role adds software to patch and a potential target for attack, so administrators usually keep the installation as lean as the job allows.

When a Website or App Needs Windows Server

Most websites do not need Windows Server. Content management systems, PHP applications and many open-source stacks run well on Linux, which is the more common choice for these workloads. Windows Server becomes necessary when the software depends on Microsoft technology.

Typical reasons include ASP.NET applications that use Windows-only features, Microsoft SQL Server databases, integration with Active Directory and business software sold only for Windows. In those cases the application decides the platform. Because Windows licensing adds to the cost of a server, it is worth confirming that the software truly requires Windows before choosing a Windows plan. For how licensing works, see Windows Server licensing.