This sensor is not really KY-007 since KY-007 does not seem to exist any more officially. However, on the internet sometimes KY-007 is associated with the PIR movement sensor, so we also used that code for this sensor. This Passiv Infra Red sensor (wiki) performs surprisingly well for its low price. But watch the connections. In my case the connections are not as default shown on the internet. In my case the power and ground are twisted, according to the images shown here.
The sensitivity and holding time can be adjusted. Sensitive Setting: turn to right, distance increases (About 7M); turn to left, distance reduce (About 3M). Time Setting: turn to right, time increases (About 300S); turn to left, time reduce (About 7S). There are no flashing LEDs or something. There is not even a power control LED. Digital pulse is HIGH when triggered (motion detected) or pulse is LOW when idle (no motion detected). Pulse lengths are determined by resistors and capacitors on the PCB and differ from sensor to sensor.
For even more information go to this Adafruit page.