FatBitsAn option in the "Goodies" menu of the first MacPaint applications. It let a user edit an image one pixel at a time. Any paint or image editing program that lets you zoom down to a single pixel is providing the same editing mode.
|The Lasso's FatBits|
|This view zooms in on the lasso button, which is displayed in its normal size at the top right. At this depth, you can edit one pixel at a time.|