Ions are molecules that have small electrical charges. These charges are positive or negative. They repel or attract each other. Opposite charges attract and similar charges repel. Table salt, sodium chloride, is an excellent example.
Sodium forms positive ions and chlorine makes negative ions.
The opposite charges attract each other and make table salt. These charges are identical to those found in batteries or static electricity, but on a much smaller scale. Individual ionic bonds are very weak, but millions of them in combination are quite strong. A surfactant with a positive charge is cationic. Anionic surfactants are the most widely used detergents in the cosmetology profession.