A feature of Microsoft Internet Explorer that allows users to designate which intranets and portions of the Internet are trusted or distrusted. The more trusted a zone is, the broader the permissions it grants for executing scripts, Microsoft ActiveX controls, and Java applets, and for executing other potentially hazardous actions. Security settings for a zone can be high, medium, low, or custom.
Here are the zones you can configure and their default security settings:
A fifth zone, which is defined as trusted but which cannot be configured, is the My Computer zone, which consists of the local system’s resources.
Graphic S-4. The Security tab in the Internet Options dialog box.