What are atomic isotopes?

Question

The definition really confuses me. Can someone give me a easy and concise one?

Answer 1

An isotope is an atom with the same number of protons and electrons as the more commonly found element, but a different number of neutrons

i.e. Hydrogen = 1 Proton & 1 Electron

Deuterium (Hydrogen Isotope) = 1 Proton, 1 Neutron & 1 Electron

Think of it like this, isotopes have the same atomic number but a different mass number.

Answer 2

it is atoms of the same element with different numbers of neutrons