As far as I know, masks have been a feature in Photoshop since before the CS versions. The option should be under "Layers" from the top cross menu. Heres a tutorial showing how to use Masks in CS. Tutorial: Introduction to Layer Masks Photoshop CS Tutorial: Introduction to Layer Masks Photoshop CS Level: Beginner Painting on a layer mask. Masks are incredibly useful for blending photos and hiding portions of images without altering them directly. In this tutorial we'll learn to use the Brush Palette and Fill Layer with Mask to make an “eraser scribble” type of image. 1. Open a new document, at least 200 dpi for good printing. Open your photograph and drag and drop with the Move tool onto your new document. 2. Make a new Solid Fill adjustment layer by clicking Layer>New Fill Layer>Solid, or click on the half black/half white circle in the bottom of the layers palette and choose Solid Fill. Choose white as the color. Photoshop: Elements: 3. Lower the opacity of the Fill layer slightly to reveal the photo underneath. 4. Choose the Brush Tool, and select a soft, round brush from the Brush Drop Down Menu. Choose Black as the Foreground Color. 5. Optional in Photoshop : Click on the Brush Palette Tab at the top right of the screen to open, and click on the word Texture to open the Texture Options. Adjust the texture scale and depth to give a slight texture to the brush, according to your taste. Pictured here is Wrinkles texture on default options. 6. Select the mask on the Fill layer (second thumbnail), denoted by the border around the mask thumbnail, and the white circle icon between the Eye icon and the Fill layer thumbnail. 7. On the mask, paint using fast zig-zagging or scribbling motions to reveal the photo on Layer 1. Type X to toggle the foreground color to White, and paint to cover the photo back over. Use the bracket keys, [ and ], to enlarge or shrink the brush size. Undo and redo the painting until you are satisfied with the results: but don't obsess! Variation with colored Fill layer, Pattern Fill layer, and the mask was painted with black and then restored with white to get cloudy look: 8. Optional: Change the opacity of the brush in the Options Bar at the top of the screen if you want to reveal less of the photograph. 9. Return the opacity of the Fill Layer to 100%. Link the photo layer and the Fill layer, then you can reposition on the canvas if needed. Notes: Layer masks are a function of opacity. Imagine putting a piece of paper over a photograph: the photo is hidden, and only the paper, or “mask” is visible. Use scissors to cut a hole in the mask paper, and reveal the photo underneath. Digital masks work in the same basic way. When you paint on the mask using black, you are “cutting” the mask away to reveal what's beneath. Any white part of the mask is opaque, and black part is transparent, and any shades of gray are varying opacities. Try changing the color and shape of the brush to experiment with the results!