Fluffy, fuzzy, short or long: Fur comes in all kinds of textures, lengths and colors, and it's a major reason why animals are so darn cute. But believe it or not, you don't actually need to draw every single strand of fur on an animal if you want it to look realistic. You don't even need to draw one strand. (That goes for human hair too, by the way.)
What you'll want to do is focus on drawing the fur as a whole, and notice how it's affected by lights and shadows. That's how you get your animals to look real — without wasting time or losing your mind drawing thousands and thousands of strands.
No matter what kind of fur you're drawing, here's your first job: Pay close attention to the direction of the strands. You'll need to shade sections of fur by moving your pencil in the same direction. Think of it as shading shapes. Your pencil shading will give the impression of individual strands, even though you're not actually drawing each hair.
Start by drawing a faint outline of the shape of each spot, putting it in the right place on your animal. That will give you a clear sense of the proportions, before you develop the fine details and shading.
If you're drawing a cow, for example: Yes, the spots look black, but you'll notice in the drawing above that each spot has variations in its tonal value. The lighter areas inside the spots are places where the light hits the cow's skin, and the fur reflects that light.
Capturing those different tonal values will make your spots look much more realistic than if you shaded all the spots in just one tone of black. They'll also give your drawing more dimension and depth.
To draw short fur with no spots (like the horse in the second example above), focus just on shading the areas in shadow. That's what short fur looks like in real life, and your drawing will capture that effect.
Ironically, fluffy fur often looks homogeneous or "flat" (see the white areas on the second close-up above). It's hard to see the individual strands when you're dealing with fluff. Those little strands of fur show up best in the places where the animal is bending and forming creases. That's because the folds make the fur look darker (as in the first close-up above).
To get that effect in your drawing, shade the areas, and draw small lines and "V" shapes to suggest individual hairs.
Pigs, goats and certain other animals have a super thin layer of fur, and sometimes it's barely even noticeable. Matching that texture in your drawing is pretty easy. All you need is some quick and simple shading to create the look of a pig's skin or a goat's white fur. It's less work to pull off, but just as realistic-looking (and cute!) as those hairier animals out there.