window close tag
This statement closes the window whose tag number is tag,
removing it from the screen. It also closes all buttons, textfields and other controls that were in the window. If you
re-use the same tag value in a subsequent window statement, a new window is created.
If you're closing the active window, and your program has other visible
windows open, one of the other windows becomes the active window, and
becomes the current output window. If you're closing the current output
window (but it's not the active window), you should explicitly
designate a new destination for output (using the window statement or the window output statement) before executing any subsequent text or drawing commands.