I was playing my guitar earlier today, everything working fine; sound coming through the amp and all.

I bought new strings strings and changed them out today and moved the guitar and amp into to a different place, but now when I play the guitar it doesn't come through the amp.

I have a brand new guitar cord, and used another to see if it would work, but nothing worked. It isn't the amp because it is turned on and when I unplug the cord from the guitar then put my finger on it it makes noise the way it would.

The only problem I could see would be with the guitar, although nothing has happened to it. What could the problem be?