So for now(2018) we human believe that Electricity is flow of elctrons from -ve(explained below) terminal to +ve(explained below) terminal, it is just that. The simple way to get this flow if by using the batteries, now lets start go to deep down.
q = n * eor ` q = e + e … n times`
Flowing electrons are called electric current, it is measured in Amperes.
120V or 220V is dangerous
Conductor are element which have small sections of electron which are free to move around conductors(again a theory we believe in).
Non-conductor all electrons are bind to atoms.
Other than battery we can use silk and glass experiment to see electric charges and some of their behaviour.
Similarly if we rub the rubber-rod with cat-fur the the rubber-rod said to have lose got electron hence move of type B charge.
Basic concepts are covered up electricity are covered up, add will keep adding them if something else comes to my mind