https://math.stackexchange.com/questions/778004/why-study-integrality https://math.stackexchange.com/questions/778004/why-study-in... There's a good explanatio

https://math.stackexchange.com/questions/778004/why-study-integrality https://math.stackexchange.com/questions/778004/why-study-in... There's a good explanation of the motivation for this concept, here.