Simple Switch Question

I have a switch/circuit that is either open (no voltage going through or closed (14V going through). I am trying to use my Arduino to select if it is open or closed. What is the best/easiest way of doing that? Can I use a relay (JZC-11F, i.e.) to do that (because its 14V assuming can't plug it in directly into the Arduino)? Thanks.

To get good answers instead of guessings or qeuistions, please post a diagram. Pen and paper is fine.
Data for the realy, or direkt link please.
A logic N-channel MOSFET could do the job.

New to the forum..thanks for the advice and suggestions. How would I use N-channel MOSFET in this scenario? Most tutorials focus on using a MOSFET to control another device vs sensing.

Okey. Put the MOSFET at rest a while. Post a wiring of the project. Your text doesn't make it clear.

How to make a schematic you can post

Being a newbie I appreciate the help, but the diagram now is essentially like this. Two wires and I need a way to know if they are open or closed. I know it's simple but know sure how else to represent.

Use a voltage divider (q.v.). I.e. Two appropriately sized resistors and connect to an analog input.

Make a voltage divider giving less then Vcc of the Arduino. 20 kOhm to +14, other end to a 10 kOhm down to GND. The middle point to an input pin of the Ardujino. Connect GND Arduino to the GND You show.

voltage-divider-calculator

Is the 14V AC or DC? How much current flows when the switch is closed? What is the switch switching?