Matter is made up of molecules, which are made up of atoms with negatively charged electrons and positively charged protons. Under normal conditions, an atom has the same number of protons and electrons, and is in a positive and negative balance, so it appears to be electrically neutral to the outside. "However, electrons surround the nucleus of an atom, and as soon as an external force is applied, they disengage from the orbit, leaving the original atom and intruding into the other atom B. Atom A is positively charged due to a lack of electron numbers, which is called a cation. Atom B is negatively charged due to an increase in electron numbers, which is called an anion.".

The reason for the unbalanced distribution of electrons is that electrons are separated from their orbits by external forces that contain various energies (such as kinetic energy, potential energy, thermal energy, chemical energy, etc.). In daily life, any two objects of different materials that come into contact and then separate can generate static electricity.

"When two different objects come into contact with each other, it can cause one object to lose some charge, such as transferring electrons to another object to make it positively charged, while the other individual gains some remaining electrons to make it negatively charged.". If it is difficult to neutralize the charge during the separation process, the charge will accumulate and bring static electricity to the object. Therefore, when an object comes into contact with other objects and is separated, it will carry static electricity. Usually, peeling a plastic film from an object is a typical "contact separation" electrification, and the static electricity generated by taking off clothes in daily life is also "contact separation" electrification.

Solids, liquids, and even gases can become electrostatic due to contact separation. Why does gas also generate static electricity? Because gas is also composed of molecules and atoms, when air flows, molecules and atoms will also undergo "contact separation" and become electrified. Therefore, in our environment and even on our bodies, there will be varying degrees of static electricity, and when static electricity accumulates to a certain extent, it will occur.