Can sompobody tell me whats wrong with my computer??

i press the poweron, and the light that indicates that the computer is on, is on. but the computer doesnt start. i do no hear the fan or the noise that it regulary makes when i turn it on. and i do not see anything on the screen. i just see that that small light is on, thats all. when i press the power on to turn it off the light comes off and thats it. can somebody tell me whats wrong with my computer. what part of it is not working.?? is it the harddrive or anything else. i have done all those tricks about pressing f8 but it doesnt work. please help meeeeeeeeeeeeeee ... i hav another laptop this is where i am writing ook