Theoretically the induction charge can be referred to as the movement of electrons to any part of the body through an electric field. In other words, if we put a neutral charge body near a body that is positively charged, this neutral body will be charged with all the negative charges of the positive and thus be charged. The Van de Graff generator is charged by induction.
On the other hand, in the contact charge there is a direct passage of electrons from one side to the other and receives the EQUAL charge to that of the body that is charged. The batteries are charged by contact.