填空题

Credit card is becoming more and more popular，because it’s very convenient．You can take it to anywhere without taking a lot of cash．For this reason，more and more people begin to enjoy using it．The followings are the steps that you operate when drawing money from the teller machine in the credit card．
1．Insert your card face up into the card slot on the teller machine．
2．Enter your six-digit identification number on the number buttons．
3．Press the button for checking or the button for saving．
4．Enter the amount of withdrawal，press the “yes” button，and wait for your receipt to be printed．
5．The drawer will open automatically with your cash and receipt．
6．Press the“Exit”button．and remove your card from the slot．
HOW many numbers does the identification password have
It is a______identification number．