For such a relatively small device, a lot can go wrong with your laptop. One of the more frustrating things that could go wrong is when your screen won't turn on. If this happens to you, here are a few ways that you could remedy the problem.
No Display on Laptop When Turned On
If you can't get the display to work on your laptop screen — even when it is switched on and the CPU fan is running — then remove the RAM from the slot, clean it, and place it back properly. (You can also try inserting it in another slot.)
If you have two RAMs inserted, then remove both and replace only one. If you check the display and it still isn't working, try switching out the RAMs.
If the problem persists, then try connecting an external monitor to your laptop. Simply look for the VGA connector (there will be a monitor symbol) on your laptop, and connect it to the external monitor. Then turn your laptop on.
If you are able to get the display to work on the external monitor, then there may be a problem with your laptop's backlight bulb or inverter, one or both of which will need to be replaced.