Screen is blank (Tablet)

You may have reduced the brightness of your screen before and forgot to increase it. For instance, if your computer had to do some processing where the screen was not required (good to save energy). 

In that case, just turn the brightness up again. Check out the don't know how to make the screen brighter solutions to learn how to increase it.

In some situations, removing the device's battery and reinserting it after a minute will fix the blank screen issue.

Note: If your device's battery is non-removable (i.e. you can't remove it), leave the device working until the battery is fully drained. After that, recharge it, and turn it on.

Maybe your screen is black because your device is not turned on, or maybe you have accidentally turned it off.

If you are using a computer and it doesn't turn on, check out the solutions to the computer doesn't turn on issue.

Your screen might be blank because your entire device didn't start. 

To check if that's the case, plug it into your computer (e.g. via USB), and wait for at least 5 minutes (because the battery might be empty) and if it is not recognized by your computer then it doesn't function properly. 

If this is the case, ask a computer repair guy to repair it.

Nowadays, you can reach most manufacturers or retailers directly via live chat, email, or direct call, and have your faulty device replaced.

Check their websites for more information regarding how to contact them.