How can I simply record footage of my game in unity?

I am very early in the making of a new game I am planning to announce with a teaser trailer. Since I am newer to unity I have been having difficulty trying to record simple camera panning that I can use in a video editor for my teaser trailer, can someone help me?

You can also use various external screen grabber programs. These are sometimes much easier to work with than stuff inside the engine + can do basic editing too as well as sound recording.

I can personally recommend ScreenFlow for Mac - or FRAPS for Windows.

There are two parts to this problem, smoothly panning the camera and recording the demo itself. For the first you can put a simple movement script on the camera. For the second you can use something like this script to spit out screen grabs you can stitch together in some other movie app.