  We study frustrated quantum systems from a quantum information perspective.
Within this approach, we find that highly frustrated systems do not follow any
general ''area law'' of block entanglement, while weakly frustrated ones have
area laws similar to those of nonfrustrated systems away from criticality. To
calculate the block entanglement in systems with degenerate ground states,
typical in frustrated systems, we define a ''cooling'' procedure of the ground
state manifold, and propose a frustration degree and a method to quantify
constructive and destructive interference effects of entanglement.
