View > Units > Pixel
You can display ruler units in pixels, inches, or centimeters. Use the Rulers command to show or hide the rulers.
1. Do one of the following:
 Choose View > Units > Pixel
 Click the Pixel button on the toolbar
Related Information
How Do I > Move Pixels in a Raster Layer
Effects > Distort > Pixelate
Tools > Move Pixels
Selection > Erase Selected Pixels
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