My parallaxing is moving by it self?

I’m trying to follow a tutorial on youtube but my parallaxing is moving by itself even if I don’t move. Here is the code, the tutorial uses a orthographic camera.

using UnityEngine;
using System.Collections;

public class Parallaxing : MonoBehaviour {

	public Transform[] backgrounds;			//Array (List) of all the backgrounds and foregraounds to be parallaxed
	private float[] parallaxScales;			//The proportions of the camera's movement to move the backgrounds by
	public float smoothing = 1f;			//How smooth the parallax is going to be. Make sure to set this above 0

	private Transform cam;					//Reference to the main Camera's tranform
	private Vector3 previousCamPos;			//The Position of the camera in previous frame


	//is called before start(). Great for referencing
	void Awake () {
		//set up the camera reference
		cam = Camera.main.transform;
	}

	//Use this for initializing
	void Start () {
		//The previous frame had the current frame's camera position
		previousCamPos = cam.position;

		//Assaigning corresponding parallaxScales
		parallaxScales = new float[backgrounds.Length];
		for (int i = 0; i < backgrounds.Length; i++) {
			parallaxScales <em>= backgrounds_.position.z*-1;_</em>

* }*
* }*
* //Update is called once per frame*
* void Update () {*
* //For each Background*
* for (int i = 0; i < backgrounds.Length; i++) {*
* //The parallax is the opposite of the camera movement because the previous frame multiplied by the scale*
_ float parallax = (previousCamPos.x = cam.position.x) * parallaxScales*;*_

* //set a target x position which is the current postion plus the parallax*
_ float backgroundTargetPosX = backgrounds*.position.x + parallax;*_

* // create a target postion which is the backgrounds current position with it’s target x postion*
Vector3 backgroundTargetPos = new Vector3 (backgroundTargetPosX, backgrounds_.position.y, backgrounds*.position.z);
//fade between current position and the target position using lerp*

backgrounds.position = Vector3.Lerp (backgrounds.position, backgroundTargetPos, smoothing * Time.deltaTime);_

* }*
* //set the previous camera position to the camera’s position at the end of the frame*
* previousCamPos = cam.position;*
* }*
}

Try replacing the second “=” in line 36 with a “-”:

float parallax = (previousCamPos.x - cam.position.x) * parallaxScales*;*