HP 3000 Manual page 290

An example of overlays and variable start line forms used together is an order entry application that
begins with a small form that occupies the top few lines of the screen to enter header information. The
next form is a one-line form that is displayed once for each detail line of the order, moving down the screen
a line at a time. The final form occupies the last line or two of the screen and contains the totals for the
order. An entire order (assume the maximum detail lines is 15) can be seen at one time even though it was
entered on many different forms.
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