The meta tag*** has two attributes. They are a content setting in the options, which can prevent browsing of some restricted websites.
The restriction level of the website is through Meta attribute is set;
Forcing the page to be displayed as an independent page in the current window can prevent Your own web page is called as a frame page by others;
< p>Set special effects when entering and leaving the page. This function is FrontPage "Format/Webpage Transition" in "Format/Web Page Transition", but the added page cannot be a frame page.