A current loop is rotated in that region of space. If at any orientation, torque acts on it then magnetic field is present there. But if current carry loop does not experience any torque then magnetic field is not present.
Electric current produces a magnetic field. This magnetic field can be visualized as a pattern of circular field lines surrounding a wire. One way to explore the direction of a magnetic field is with a compass, as shown by a long straight current-carrying wire in. Hall probes can determine the magnitude of the field.