What is electrical charge and how is it different from electric energy? I am a grade 12 student, and my textbook  mentions

Charge is always associated with mass.

Why does charge need to have mass associated and not the other way around necessarily?
Also , if mass is a form of energy (E=mc2),then should not charge be too(as it can not exist without mass),if so what is the difference between charge and electrical energy ?
 A: 
what charge actually is, and why is it that charge is always associated with mass (but not necessarily the other way around)


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*A charge is a subatomic particle with an electric field around it. The particle and the field form a unit.

*The electron has a negative unit of electric field around it and the proton has a positive unit around it.

*If one separates the charges, one obtains general and easily measurable fields. If you put a current-carrying wire (a piece of metal with its loosely bound electrons) between the separated charges, a current flows.

Subatomic particles are the carriers of the electric fields. Electric fields without sources do not exist.
This is an assumption based on our observations and is so strong that it has been elevated to the status of a law.

what is the difference between charge and electrical energy

You get electrical energy when you separate charges. The more you separate, the more they tend to flow back to equilibrium. Every atom wants to balance its charges in the nucleus and in the shell.

A bit history
By rubbing materials and collecting the electricity in a Leyden jar, scientists learned to create an electric current. They achieve the same result with insulated chemical compounds, with a current flowing between the connections.
At the end of the 19th century, J. J. Thomson discovered the electron. He came to the conclusion that these rays consist of negatively charged particles, which he called "corpuscles", later renamed electrons.
Electrons and their electric field
Electrons are massive particles and they obey an electric field. This field usually is compensated be the opposite electric field of the protons inside the nucleus of atoms.
A lot of elements called metals and metal-like and their electrons are loosely bonded inside the atoms. Beside rubbing and using chemical processes the electromagnetic induction is the main technology to separate charges. Using the interaction between external magnetic fields and the electrons own magnetic field lead to the deflection of electrons. This is used to separate them from the nucleus and to get an electric potential difference.
Electrons indeed are flowing (direct current DC) or oscillating forth and back (alternating current AC), so the name electric current was happily chosen.
