Wtf? My sound is gone!

When I got onto my computer today, there was no sound, I double checked to see if the mute was on or if the sound was up, or even if my headphones were plugged in. All were go. So I restarted my computer twice...still nothing. So I naturally assumed my headphones crapped out on me. I just got back with new headphones, and still no sound! So apparently its the computer....any advice to help me out?

system restore to when it did work

How do I use system restore? Ive never used it before...

are your sound drivers installed? i accidentally uninstalled mine once. 

I used system restore and now my sound works again! Thankyous :D