high pitched noise on booting
 

I am new to Ubuntu.When I booted up today all I got was a high pitched extremely unpleasant sound which I only stopped by taking the battery out! What is happening. I also have windows which boots up with no problems.
Please help
I am on a laptop. sound is continuous, than pitch varies and very unpleasant.Black screen with lots of writing ( sorry I am very new ) and does not boot up. Waited for few minutes but could not tolerate noise and feared for my computer!

So you're on a laptop?
when exactly does it happen? no messages displayed or anything?
Out of curiosity, is the sound a constant sound, or is it jittery (like a whole bunch of beeps coming right after each other)?

there was lots of messages but I am afraid they made no sense to me as I am new. The end word was failed!It did not boot. Just stopped. What shallI do?