Selects irregular areas. To add to the current selection, hold down the shift key. To subtract from the current selection, hold down the command key.
Marquee tool
Selects rectangular areas. To add to the current selection, hold down the shift key. To subtract from the current selection, hold down the command key.
Bucket tool
Fills areas with a color or pattern.
Pencil tool
Draws freehand lines. Normal drawing uses the foreground color; if you click on a pixel that is already that color, the background color is used to erase.
Text tool
Allows you to add text to the icon. While you are editing the text, use the arrow keys to move it around.