Miso is itself not a
soup (as the esteemed
Pseudo_Intellectual suggests).
Miso soup, or
miso shiru, is the soup. Miso itself is a
thick paste made from
fermented soybeans. It comes in several
colors, from
yellow-
white to
red to dark
brown. It is quite high in
protein, as are most
soy products.
One important tip to remember when cooking with miso: do not boil anything containing miso, including miso soup. (This is why all good miso soup recipes specify to add the miso at the end, after turning down the heat.) Boiling will ruin the flavor of miso.