Definition:Induced Charge

Definition
Let $B$ be a body made out of an electrically conducting substance.

Let $B$ be in the shape of a slab with two parallel surfaces $P_1$ and $P_2$.

Let $B$ be placed in an electric field $\mathbf E$ acting perpendicular to $P_1$ and $P_2$.

The surface charges on $P_1$ and $P_2$ caused by $\mathbf E$ are called induced charges.

Also see

 * Electric Field induces Surface Charge in Conductor