How could Shake camera?

I want to make an earthquick in my game , so I want my camera to shake , I mean just like when earthquick comes everything shakes. Can anyone help me?

whoa, this is a fun question!!! i gave you some variables in the inspector to adjust to your liking. put this in your scene and push the spacebar

	public float speed = 1.5f;
	public float distance = 5;
	public float duration = 7;
	float timer;

	Vector3 v;
	Vector3 vs;
	Transform cam;
	void Start (){
		rand ();
		cam = Camera.main.transform;}

	void Update(){
		if(Input.GetKeyDown("space")){timer=duration;vs = cam.position;}


		if(timer>0){timer-=Time.deltaTime;
			cam.transform.position=Vector3.MoveTowards(cam.transform.position,v+vs,speed*timer*Time.deltaTime);
			if(cam.transform.position==v+vs){rand();}}}
	void rand (){
				v = new Vector3 ( Random.Range (-distance, distance),
		                          Random.Range (-distance, distance), 
		                          Random.Range (-distance, distance));}