My screen went black but if I shine a light on it I can see it? What do I do?

Question

My screen went dark but I can barely see it if I shine a light on it. I tried to find my mouse on the screen but can't

Answer 1

If you have a VGA display and a correct display adapter, you should be able to see the computer's desktop and access it there.
The http://ifixit.com site has various repair guides and as a reference, you could look into the proper one for your model and build version of Mac to see what they say. Some users of their site contributed comments in a few of them.
http://www.ifixit.com/Device/Mac_Laptop
Details are important, since the model number may represent many years of changes, and not tell exactly what one you have. And the serial number in your computer can be used to identify-by-serial number, information on the model you have, its configuration as shipped, year, etc.
http://www.powerbookmedic.com/identify-mac-serial.php
Or try & find it at http://everymac.com database.
There are circuits, and cables that flex when the display lid is closed, plus another one that sits by the logic board that support display function, so one of these probably has failed. It would require an authorized repair or someone very handy and experienced in this design of portable computer repair. I doubt a casual user would be able to replace the correct parts; then without causing another kind of issue if they messed up some other parts that currently are not contributing to the symptom you noted.
Troubleshooting is something an expert can do. But you can use the computer with a second display so long as you have an adapter that will work with the kind and type of ports and plugs that are there. Other adapters exist that may not work, but can look very much like those what do.
Good luck & happy computing!
{edited to add links}