12V and 240V sockets, what's the difference?

12V and 240V sockets not only differ in their voltage but also their plug in interface.  Below is an image of each and a few notes on what purpose each of them will serve in your camper conversion. 

12V socket. formerly know as a cigarette lighter socket. 
This is wired to the leisure battery and is usable all of the time.
It's often used for cool boxes, chargers for various devices and sometimes for plugging in a 12V TV.
240V socket.
This will only be active when you're hooked up to a mains supply. Then you can use conventional 240V electric appliances like your laptop, 

So when we're making the distinction between a 12V socket and a 240V socket, not only is their supply voltage different, but the actual plug in style is different too, making sure it's not possible to plug the wrong item into the wrong voltage. 

Thanks for reading, have a great day!