A small graphic that represents a larger image. Thumbnails are often used in palettes to give a visual history of the states in the image.


The grayscale values from 0 to 255 that differentiate an image's pixels. Tonality is black and white and shades of gray; tonality is one of the most expressive elements in an image. If you want to create a strong feeling in an image, consider exaggerating the tonality in some way.

tool preset

A user-defined set of tool parameters accessible through the Tools Preset palette. Options bar information, foreground color, and external palette information (where applicable) can be saved as part of a tool preset.


The spacing between entire lines of letters.


To modify the position, scale, or proportions of a layer. Transforming a layer is useful for changing the size or placement of a layer, as well as for adding perspective or distortion.

transparency checkerboard grid

The checkerboard background that appears "through" an image when you have made some part of an image transparent. You can control the size and color of the checkerboard grid using the Preferences dialog boxes.


A grayscale image to which are added two colors for a total of three colors (or plates).