You press the power button and nothing happens? Does your device not respond? Does your iPod just display a black screen? Do not worry. This can be easily fixed in a few seconds.
Here is how to restart your unresponsive iPad touch:
1-It may be that your battery is completely drained. If your device’s battery is totally dead, it won’t respond. If this is the case, your device will not work until it is charged. To resolve this issue, connect your device to a wall charger and let it charge for at least 15 minutes. Your device will turn on itself. If it is not, make sure that charging cable is not defective. You may want to try a different charger/cable.
2-It may be that iOS suffered a crash and needs to be rebooted. To resolve this, reset your device by pressing and holding the home and power (aka sleep/wake) buttons at the same time until you see the Apple logo. Release the buttons when you see the logo.
If you are still having issues, you may want to contact Apple support.