Cations, anions?

What do the terms cations, anions and non-ions mean?

Anions are negative ions.
Ordinary cleaning products (tensides) are anionic, negatively charged.

Cations are positive ions.
There are cationic tensides such as Benzaltenside.
These are positively charged and also poisonous to microorganisms.
Are used in bactericidal cleaners and as the active substance in pesticides.

If cations and anions are mixed they cancel out each other, mixing plus and minus gives a zero result.

There are also non ionic tensides, cleaning agents without a charge (neutral).
These do not affect anionic or cationic tensides or cationic polymers. Used
for cleaning prior to cationic surface protection and for maintenance washing.

Cationic polymers are positively charged.
Nothing can grow on treated surfaces.