It adds a camera and a plane and they are sticked together both rotation and location wise.
If you want to add effects to your animation e.g. noise, boiling effect; create a new material to the plane and apply the effect.
The effect is on top of the animation and you can see through it.
If you want to move the plane further or closer to the camera, hit G, it will move on the local z axis only because the other ones are locked, so you don't have to hit G+Z or whatever.
Check out Serpens which is an addon creation tool using nodes instead of code.
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