Static electricity is discussed in the document. It occurs when there is an imbalance of electric charges on the surface of materials. Friction from objects rubbing together can cause a transfer of electrons between the objects. One object gains negative charge by gaining electrons, while the other gains positive charge by losing electrons. Examples of static electricity include balloons sticking to walls after being rubbed with hair. Conductors allow electron flow while insulators retain static charges. Van de Graaff generators produce large static charges. Applications include filters and dangers include shocks if charges are not discharged to ground.