What does the thumb direction represent in the right-hand thumb rule? What sets this rule distinct from Fleming's left-hand rule?

The current in the conductor is shown by the direction of the thumb in the right-hand thumb rule.

The right-hand thumb rule varies from Fleming's left-hand rule. In Fleming's left-hand rule, the thumb symbolizes the force on the conductor, the forefinger represents the magnetic field, and the middle finger represents the current. The thumb orientation in the right-hand thumb rule represents the current in the conductor, whereas curled fingers represent the magnetic field direction.