Target frame names that have special meanings to browsers
  1. "_self"   (Same Frame) sets the target frame of the hyperlink to the same frame that contains the hyperlink. Use this setting to override the page's default target frame.
  2. "_top"  (Whole Page) sets the target frame of the hyperlink to the entire Web browser window.
  3. "_blank"  ( New Window) specifies that a new instance of the Web browser should be launched on the user's desktop, and the page that is the target of the hyperlink should be displayed in the new instance of the Web browser.
  4. "_parent"  (Parent Frame) specifies to display the page that is the target of the hyperlink in the frame that contains the current frameset tag. This is an advanced feature.
  5. If a name other than the values specified above is chosen, a new browser window is spawned when the first link is followed. All followed links will be displayed in the new window.