Target This property specifies the open mode of the link to the browser window, its parameter value mainly: _blank, _parent, _self, _top, these parameter values The meaning of the representative is as follows: ◎ _blank, open in the new browser window Link file. ◎ _Parent, load the link file into the parent frame set or parent window containing the link frame. If the frame containing the link is not nested, the link to the link is loaded in the browser full screen window, just like the _self parameter. ◎ _Self, open the links of the link in the same frame or window. This parameter is the default value, usually no specified. But I don't quite understand ◎ _top, open the links of the link in the current entire browser window, so I will delete all frames.
default open mode: This page opens Open mode: New window open body> html>
Add some point: Target = mainname replaces the mainname to your target file, will be displayed in the target framework.