The world is made up almost entirely of atoms.
In order to understand about radiation, you have to know about "atoms" and "ions".
This page introduces atoms and how atoms turn into ions.

　　

Atoms

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An atom is a particle unit that makes up a substance.
An atom is constituted of an atomic nucleus and electrons.
The atomic nucleus is the center of atom.
Electrons fly around the center of the atom.
Moreover, the atomic nucleus is constituted of protons and neutrons.
Protons have a positive electric charge and electrons have a negative electric charge.
Their electric power is equal.
Neutrons aren't electricity.
Protons and electrons are the same in the atom so the atom is neutral.

Moreover, protons's mass and neutrons's mass are same,
however the electrons's mass is 2000/1.
Therefore an atom's mass is decided by the total of the proton's mass and neutrons's mass.


　　

Ions

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According to the previous sentence, an atom hasn't usually electricity,
because protons and electrons have the same number.

However, electrons fly around the atom,
and electrons deviate from the atom due to the effects of something.
In contrast, other electrons bump against the atom.

When an atom lets go of electrons, the atom takes a positive charge.
When an atom gets electrons, the atom takes a negative charge.
This way when an atom takes a positive electric charge or negative electric charge it's called an "ion".

Positive charges and negative charges attract each other,
but two positive charges repel each other as do negative charges.

An ion that takes a positive charge is called a "positive ion"
and an ion that takes a negative charge is called a "negative ion"