Definition
A group is quasisimple if it is equal to its commutator subgroup and its inner automorphism group is non-abelian simple. All non-abelian simple groups are quasisimple.
Definition
A group is quasisimple if it is equal to its commutator subgroup and its inner automorphism group is non-abelian simple. All non-abelian simple groups are quasisimple.