Short answers, pulled from the story.
The Copenhagen interpretation is a collection of views about the meaning of quantum mechanics, stemming from the work of Niels Bohr, Werner Heisenberg, Max Born, and others. Its core claims include that quantum mechanics is intrinsically indeterministic, that probabilities are calculated using the Born rule, and that no truth can be attributed to an object except through the results of measuring it.
Werner Heisenberg coined the term around 1955, using it while criticizing alternative interpretations of quantum mechanics, including one proposed by David Bohm. Heisenberg later privately expressed regret for using the term, because it implied the existence of other interpretations, which he considered nonsense.
No. Bohr and Heisenberg disagreed on several important issues, including the nature and placement of the boundary between quantum and classical domains and the meaning of wave-particle duality. Bohr distanced himself from what he considered Heisenberg's more subjective interpretation, and their writings contradict each other on several points.
The Born rule, formulated by Max Born in 1926, gives the probability that a measurement of a quantum system will yield a given result. In its simplest form, it states that the probability density of finding a particle at a given point is proportional to the square of the magnitude of the particle's wave function at that point. It is essential to the Copenhagen interpretation as the mechanism linking the wave function to measurable outcomes.
Einstein maintained that quantum mechanics could not be a complete theory. In a 1935 paper with Boris Podolsky and Nathan Rosen, he argued that quantum mechanics failed to account for elements of physical reality that must exist prior to measurement. He also rejected the indeterminism of quantum theory, famously saying he was convinced that God does not throw dice.
The Copenhagen interpretation has been the dominant view throughout much of the 20th century and remains the most widely accepted label physicists apply to their own views. Informal polls conducted at quantum mechanics conferences in 1997, 2011, and 2025 all found the Copenhagen interpretation to be the most commonly chosen position.