No audio output device is installed

Hello,

I have an HP G60-243DX notebook and a few days ago I inadverdently turned off the sound on the computer, and by that I think I accidentally may have erased my sound device from the computer.

I was trying to adjust the sound and when I went to what I thought was volume control, I thought I had found the way to simply turn the sound off for now, but instead I think the computer completely erased the sound option.

I really know next to nothing about computers so it would be nice if I could get some advice on what to do.
When I go to playback options on my computer, there are none, it just says no audio devices are installed and I can't seem to track what happened to it. I just hope I don't have to buy any new software for the computer because of one really stupid mistake.

Can anyone help me?