Display device includes timing controller, display panel, data driver, and scan driver. The timing controller includes an authentication processing unit configured to generate an authentication result based on an authentication control signal. The timing controller converts an input image data signal to data driver control signal and scan driver control signal when the authentication result represents success. The timing controller deactivates the data driver control signal and the scan driver control signal when the authentication result represents fail. The display panel includes plurality of pixels. The data driver generates plurality of data signals based on the data driver control signal and provides the data signals to the pixels through plurality of data signal lines. The scan driver generates plurality of scan signals based on the scan driver control signal and provides the scan signals to the pixels through plurality of scan signals lines.