Scan driver and scan signal driving method and organic light emitting display using the same

An organic light emitting display, comprising:

• a pixel portion having at least one pixel coupled to a data line and a scan line;
• a data driver configured to provide a data signal to the data line;
• and
• a scan driver configured to provide a scan signal to the scan line,
• wherein the scan driver includes:
• a plurality of stages coupled to each other in series, each of the stages configured to receive a clock signal, a clock bar signal, and an input signal, wherein each stage includes a first circuit that is configured to:
• store a first voltage and a second voltage in response to the input signal and one of the clock signal or the clock bar signal, the first voltage and the second voltage each corresponding to a voltage of the input signal, and
• provide a first output signal that corresponds to the second voltage in response to the second voltage and the other of the clock signal or the clock bar signal.