QUESTION about Masks

In relation to what? The concept of 'masks' are used in different contexts; Photoshop and other image editors use them to reference an area of an image, to hide it, prevent it from being edited,etc. Some applications use masks for transparency, or to map where different elements, like buttons should be drawn.

Masks of the 'ski' variety are the choice of professionals in the robbing of banks, gas stations, convienence stores, etc, and the 'gas' variety are good to keep on hand as well.

If you are talking about masks in WindowBlinds skins, they are used for custom color support. The mask tells WindowBlinds which areas to colorize and how much. Black areas of the mask are not colored at all, and white areas are colored 100%.

The masks are selections of a image, normally saved inside the image file. You can apply this masks as a selection for further changes. The most use applied to masks is to hide part of an image (for example, selecting a person on a landscape); when you make a selection (normally viewed as a discontinuous line), you are making a mask, if you save this selection into the image, the selection is a masks. On cinema, some scenes are filmed with the background colored different as the scene (normally blue), for easy selection of persons or others and composite on post-production. This colour-contrast are intensive used on skinning, to indicate wich colours are transparent (the most colours used are magic-pink or black), and some programs (such Photopaint) uses the colour-transparency as a mask.