Set any of the following target values:
_blank Opens the destination document in a new unnamed window.
_parent Opens the destination document in the parent window of the one displaying the current document.
_self Opens the destination document in the same window as the one in which the form was submitted.
_top Opens the destination document in the body of the current window. This value can be used to ensure that the destination document takes over the full window even if the original document was displayed in a frame.