Problem:

I've connected my camera to my PC with a USB cable, but nothing has happened.

Solution:

USB Cameras generally appear as 'Removable Storage' inside My Computer.

Cameras will always have a folder at the top level called DCIM.

Take a look at all the removeable storage devices in the My Computer screen - and one is likely to have a DCIM folder - the photos are likely to be in there.  They can then be copied to your PC like normal files.