  An abstract $(v_k,b_r)$-configuration is a pair of finite sets of
cardinalities $v$ and $b$ with a relation on the product of the sets such that
each element of the first set is related to the same number $k$ of elements
from the second set and each element of the second set is related to the same
number $r$ of elements in the first set. An example of an abstract
configuration is a finite geometry. In this paper we discuss some examples of
abstract configurations and, in particular finite geometries, which one
encounters in algebraic geometry.
