  We calculate the analytic expression for geometric measure of entanglement
for arbitrary superposition of two $N$-qubit canonical orthonormal
Greenberger-Horne-Zeilinger ($GHZ$) states and the same for two $W$ states. In
course of characterizing all kinds of nonclassical correlations, explicit
formula for quantum discord (via relative entropy) for the former class of
states has been presented. Contrary to the $GHZ$ state, the closest separable
state to the $W$ state is not classical. Therefore, in this case the discord is
different from the relative entropy of entanglement. We conjecture that the
discord for the $N$-qubit $W$ state is $\log_2N$.
