The electric charge is a force of the elementary particles. It is based on the fact that atoms can have an excess of electrons or protons.
If atoms have an excess of electrons, then the negative charge predominates; if there is an excess of positive protons, the positive charge predominates. The excess charge can be created and influenced by supplying energy such as emissions or light influences and tries to balance itself out. In this process, electrons migrate from the electrode with excess potential to the other electrode with lower potential. This means that a charge with an excess of electrons tries to balance itself with one with a shortage of electrons.
According to the laws of physics, equal charges repel each other, on the other hand, opposite charges attract each other. The difference in charge between two electrical charges is the voltage (V).