This example demonstrates the visual impact of SVG masks, using them to selectively reveal or hide overlapping shapes. It creates a full-screen canvas filled with horizontal and vertical stripes by generating one hundred thin rectangles for each direction. A circular mask isolates a central area where the stripes remain visible, while a second, inverted mask produces a contrasting ring effect by revealing the vertical stripes outside the circle. The code builds the SVG document dynamically through the Document Object Model, creating elements like rectangles and masks using `createElementNS` and `setAttribute` within JavaScript.