Charging by Induction
When charging a conductor by induction, a charged object is brought close to but does not touch the conductor. In the end the conductor has charge of the opposite sign as the charge on the object.
One way to carry out the four-step process:
Bring the charged object close to, but not touching, the conductor. Charge on the conductor shifts in response to the nearby charged object.
Connect the conductor to ground. Ground is basically a charge reservoir - anything that can give up or receive charge without noticing the change. Electrons flow from ground to the conductor if the charged object is positive, and the opposite way if the object is negative. The conductor now has a net charge with a sign opposite to the sign on the charged object.
Remove the ground connection. The transferred electrons can't get back to where they came from.
Remove the charged object. The net charge distributes itself over the surface of the conductor.