# Definition:Generated Normal Subgroup/Definition 2

## Definition

Let $G$ be a group.

Let $S \subseteq G$ be a subset.

The normal subgroup generated by $S$, denoted $\gen {S^G}$, is the subgroup generated by the set of conjugates of $S$:

$\gen {S^G} = \set {g^{−1}sg: g \in G, s \in S}$