PREV Tag
The <prev> tag is used to navigate back to the previous URL on the history stack.
If there is no previous URL, processing stops and an error message may be displayed.
All URL addresses that have been visited during the current user session are stored in a history stack.
As each new URL is visited, the address is added (pushed) on to the stack.
Therefore, the history stack lists the URLs in order of visitation.
If you navigate backwards, the top URL address is removed (popped) off of the stack.
The <prev> tag can only be nested inside the <anchor> and <onevent> tags.
†Note that this example does not work on the TagTag microbrowser.
