What is the Universal law of gravitation?

Force of attraction between two masses \(m_1\) and \(m_2\) is given by,

$$ F = \frac{m_1 m_2}{r^2}$$

Where,
r is the distance between two masses \(m_1\) and \(m_2\).
G is a constant, called the Universal gravitational constant.

That is called Universal law of gravitation.