Assets/Scripts/PlayerController.cs(10,27): error CS0246: The type or namespace name `RigidBody' could not be found. Are you missing a using directive or an assembly reference?

I have read all the example scripts and they do not reference a component within the game. The script I am trying to run references the component ‘RigidBody’ and errors out when trying to test movement on a character in the game.

using UnityEngine;
using System.Collections;

public class PlayerController : MonoBehaviour {

public Rigidbody rb;

void Start ()
{
    rb = GetComponent<RigidBody>();

}

void FixedUpdate()
{
    float moveHorizontal = Input.GetAxis("Horizontal");
    float moveVertical = Input.GetAxis("Vertical");

    Vector3 movement = new Vector3 (moveHorizontal, 0.0f, moveVertical);

    rb.AddForce(movement);
}

}

This:

rb = GetComponent<RigidBody>();

should be this (notice the lowercase b):

rb = GetComponent<Rigidbody>();