  Let $A$ be an abelian topological $G$-module. We give an interpretion for the
second cohomology, $H^{2}(G,A)$, of $G$ with coefficients in $A$. As a result
we show that if $P$ is a projective topological group, then $H^{2}(P,A)=0$ for
every abelian topological $P$-module $A$.
