Questions on Quantization

1. What does "quantization" mean? What is a quantum?
2. Give some examples of quantized properties of everyday type things.
3. What property of light is quantized? What is its smallest amount?
4. What properties of atoms are quantized?
5. In what way is atomic quantization different from quantization for light?
6. What are atomic energy levels?
7. What is the "ground state"?
8. What is an excited state?
9. How many excited states does an atom have?
10. What is the energy continuum in the context of atomic energy?