* If {{Parameter|imageHandle&}} is omitted, it's assumed to be the handle of the current [[SCREEN]] or write page.
* To get the height of the current program [[SCREEN|screen]] window use zero for the handle value or nothing: {{Parameter|lines&}} = [[_HEIGHT]](0) ''or'' {{Parameter|lines&}} = [[_HEIGHT]]
* If the image specified by {{Parameter|imageHandle&}} is in text only([[SCREEN]] 0) mode, the number of characters per row is returned.
* If the image specified by {{Parameter|imageHandle&}} is in graphics mode, the number of pixels per row is returned.
* If {{Parameter|imageHandle&}} is an invalid handle, then an [[ERROR Codes|invalid handle error]] is returned.
* The last visible pixel coordinate of a program [[SCREEN|screen]] is '''[[_HEIGHT]] - 1'''.