Electric Charge

Every object usually contains equal amounts of positive charge (protons) and negative charge (electrons).
Because the charges cancel out, the object is said to be electrically neutral.

However, if for some reason there is a charge imbalance in the object, that is the total charge is not zero anymore: the object becomes charged and can interact with other objects: for instance, it will attract dust, cause sparks, etc.

This phenomenon caused by a charge imbalance is usually called static electicity (although there is nothing static about it!).