How to make the camera only move on the x axis?

I don't know how to achieve this, it will be used for camera panning. I just need someone to tell me how. (you don't have to write a script)

Well, there are several ways to approach this;

1. Make a custom script to rotate the camera
2. Set the other axis to a value that won't change
3. Make a part for the camera to get the angle of instead of making a custom script

I prefer second way because it's easy and simple to do.