explain the phenomena of induction of charges

When a charged object is brought closer to an uncharged body, separation of charges takes place in the body. Due to this the uncharged body gets attracted towards the charged body.

In charging by induction the two bodies are not in contact with each other, whereas in charging by contact the charge on one body is shared by the two bodies. 

In induction a charge of opposite sign is created without the charged body losing any of its own charge.