  An integral domain $D$ is a $v$--domain if, for every finitely generated
nonzero (fractional) ideal $F$ of $D$, we have $(FF^{-1})^{-1}=D$. The
$v$--domains generalize Pr\"{u}fer and Krull domains and have appeared in the
literature with different names. This paper is the result of an effort to put
together information on this useful class of integral domains. In this survey,
we present old, recent and new characterizations of $v$--domains along with
some historical remarks. We also discuss the relationship of $v$--domains with
their various specializations and generalizations, giving suitable examples.
