  Given a variety of universal algebras. A method is suggested for describing
automorphisms of a category of free algebras of this variety. Applying this
general method all automorphisms of such categories are found in two cases: 1)
for the variety of all free associative K-algebras over an infinite field K and
2) for the variety of all representations of groups in unital R-modules over a
commutative associative ring R with unit. It turns out that they are almost
inner in a sense.
