New to Python

[sparkz_alot]

Really?  When I run:

print ("Its fleece was white as {}.".format(snow))

I get:

Error:
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
NameError: name 'snow' is not defined

In your first example, the '{}' acts as a place holder for the elements in the '.format()' segment, in this case it is looking for the variable named snow.

snow = "snow"
print("It's fleece was white as {}".format(snow))

Output:
Its fleece was white as snow.

In your second example you are simply printing the string "Its fleece was white as snow."

Please see String Formatting