How can like and unlike charges be applied to today's society? Give two examples and explain?

Friend, Like and Unlike charge as you talk'n of physics is the basic thing we've today. Electricity is all about like and unlike charges,which makes the backbone of our present development at affordable prices.The most Important thing about like and unlike charges Is that they are used in our every day life and if you have a black and white TV, check that it's display is prepared by Electron discharge beam.
It's in almost every mechanics, the use of like and unlike charges.