Microsoft Knowledge Base Article 313434 contains the following summary:

This step-by-step article describes how to define security templates in the Security Templates snap-in.

You can configure Windows 2000 system security by applying security templates. Security templates are text-based files that contain security settings for all of the security areas that are supported by the Security Configuration tool set. The Security Configuration tool set includes the following components:

The Security Templates MMC snap-in
The Security Configuration and Analysis snap-in
The Secedit.exe command-line utility
Security Settings extension to Group Policy

Security Templates can be used as provided, or you can create your own custom security templates by modifying the configuration of the built-in security templates. After you make changes to the security template, you can apply the changes to the system configuration. Security Templates can be applied to a local computer, a domain or an organizational unit.