Measurement
One shot returns one classical bit, sampled from the state's probabilities; finite counts fluctuate around the ideal distribution with a typical error that shrinks like 1/√N. Measurement also updates the qubit to the basis state that was observed.
What does one measurement give you?
A shot is one complete execution of a circuit followed by one measurement. It returns one classical bit string — nothing more.
For a qubit in the state α|0⟩ + β|1⟩, a shot reads 0 with probability α squared and 1 with probability β squared (squared magnitudes if the amplitudes are complex). It does not return α or β.
Run many shots and you get counts, such as 487 zeros and 513 ones. Counts are samples drawn from the ideal distribution; they are evidence about the model, not the model itself.
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