When you press the power button on the iPad, even if your tablet's screen is off, the system on the tablet is actually running. To save battery, you can turn off iPad completely when you're not using your tablet. You can also turn off iPad completely, or perform an iOS system restore to fix an unresponsive iPad.
Step
Method 1 of 3: Turning Off iPad

Step 1. Press the power button on the top right of the iPad

Step 2. Hold down the power button until the slide to power off button appears at the top of the screen
Slide the switch to turn off the iPad. You may need to press the button for a few moments until the slider appears on the screen.
If iPad doesn't respond even after you press the power button, read the next section of this article

Step 3. Slide the slide to power off button to turn off the iPad

Step 4. Restart the iPad by pressing and holding the power button until the iPad screen turns on
Method 2 of 3: Restarting an Unresponsive iPad

Step 1. Press and hold the Home button
To resolve an unresponsive iPad, you may need to restart the iPad. To get started, press and hold the Home button.

Step 2. Press and hold the power button while pressing the Home button
Do not release both buttons.

Step 3. Press both buttons for approximately 20 seconds until the Apple logo appears on the screen
If your iPad won't turn off after pressing that key combination for a minute, read on for the next steps

Step 4. Wait a few moments for your iPad to finish loading the operating system and display the home screen
After that, turn off the iPad by following the first part of this article.
Method 3 of 3: Accessing Recovery Mode on iPad

Step 1. If your iPad is not responding, use recovery mode to reset iPad
After a reset, all data on iPad will be erased, and iPad will return to factory settings. Therefore, only use this step as a last resort.

Step 2. Connect iPad to your computer, then open iTunes
You will need to use iTunes to complete the iPad recovery process.

Step 3. Press and hold the power button while holding down the Home button for about 10 seconds, until the Apple logo appears on the screen

Step 4. Press both buttons until the iTunes logo appears on the screen
iTunes will ask you to restore the device.

Step 5. When prompted, click Update in the iTunes window
The program will download the latest iOS update, then install it to the iPad without deleting the data on it.

Step 6. If the iPad is still not responding after the update process is complete, repeat the above steps from the beginning, but click Restore in the iTunes window
However, this process will erase all data on the iPad.

Step 7. Once the restore process is complete, set up your iPad like setting up a new iPad
Enter your Apple account to recover data from iCloud. If iPad is still connected to iTunes, you can restore a backup of iPad data from your iTunes library.