Coats

1. Stock hair, or normal, double coat	short or "close" to medium length
	a little longer length and fuller look or "plush"
2. Long stockhair, or long stock coat, also a double coat, can be distinguished by long tufts, or 'feathering' of hair on the ears and the backs of the legs and tail.
3. Longhair, single coat, rare

Colors

Sable, agouti, or gray (wolf) Sables are born with more tan, black tipping increases in patterns similar to the two tones until the puppy is about 2 or 3 years old. Often resemble two-tones, but individual black hairs have more than one color.	Two tone Two tones are born nearly all black, and marking colors continue to come in for the first few years of life. Individual black hairs are mostly black, but graying throughout the coat, especially the neck area, can also appear.	Solid color Solids are one color at birth and stay that way.
Red Sable	Black/red	Black
Tan Sable	Black/tan	Blue
Cream Sable	Black/cream	Liver
Silver Sable	Black/silver	White, dark eyes, black noses & pads
Golden, rare		Albino
Marking color diluted sable*	Diluted black/marking color*

Diluted colors: blue, liver, fawn (not linked to any genetic disorders as sometimes earlier believed)
Marking colors: red (brownish-red), tan, cream, silver (almost white)

artist's Linda Shaw's illustrated comparisons: http://shawlein.com/The_Standard/07_Colour_&_Pigment/Colour_&_Pigment.html

Color Patterns

Saddle back	No mask
Medium blanket	Small black mask (muzzle only)
Large blanket	Medium mask
Bi-color or pointed	Dark mask

more examples of GSD colors and coat patterns: http://www.nwk9.com/type_comparison.htm

Sites to visit :

www.bluedogs.8m.com -all about the Blues

http://www.whitegermanshepherd.org/wgsdciq.htm -good Q & A section on Whites

http://siriusdog.com/color-sable-genetics-breeding-shepherd-grau.htm -renowned GSD expert Fred Lanting helps explain color differences and exposes some myths associated with the sable coloring