In the lingo of Server Manager, features are operating system components that cross role boundaries. If a role is analogous to a job title, a feature is analogous to a job skill. Some skills are useful no matter what your role is.

For example, a server that uses the BitLocker full volume encryption feature will be more secure, whether it performs the role of a DNS server or that of a file server.

The Telnet Server feature will allow Server 2008 to host incoming telnet connections, whether the server holds the role of a domain controller or that of a Web server.

The Remote Server Administration Tools feature lets you install administrative consoles even if the related service isn't running on your server. For example, if you want to administer DNS on a remote server, but you don't want to install the DNS service on your local server, you could just install the DNS console by selecting it under the RSAT feature.

As with roles, you install features via wizards launched from Server Manager. Generally, the installation of a feature is simpler and quicker than the installation of a role.

See this month's posts:

Configuring a Role in WS2008: NOT as easy as can be

Adding a role to WS2008: Easy as can be

The purpose of roles in Windows Server 2008

Meet Windows Server 2008 'Server Manager' -- your new management cockpit

The Look and Feel of Server 2008