What is the Atwood machine acceleration formula and how is it used to calculate the acceleration of the system?

The Atwood machine acceleration formula is a (m2 - m1) g / (m1 m2), where a is the acceleration of the system, m1 and m2 are the masses of the two objects, and g is the acceleration due to gravity. This formula is used to calculate the acceleration of the system by plugging in the values of the masses and the acceleration due to gravity.