  We describe the weight filtration in the cohomology of toric varieties. We
present a role of the Frobenius automorphism in an elementary way. We prove
that equivariant intersection homology of an arbitrary toric variety is pure.
We obtain results concerning Koszul duality: nonequivariant intersection
cohomology is equal to the cohomology of the Koszul complex $IH_T^*(X)\otimes
H^*(T)$. We also describe the weight filtration in $IH^*(X)$.
