how does the car move forward

#pragma strict

var speed : float = 50;
var turnSpeed : float = 2;
function Update ()
{
//this is the forward speed that will actually happen
var steer=Input.GetAxis(“Horizontal”);
var gas=Input.GetAxis(“Vertical”);

if (gas!=0)

var moveDist=gasspeedTime.deltaTime;

//turn amount
var turnAmount = Input.GetAxis(“Horizontal”)*turnSpeed;
//rotate the vehicle
transform.Rotate(0,turnAmount,0);
}

The above is the script i used to make the car move but the car only rotates around its axis (y-axis) it does not move forward.
how can i solve this?

Put transform.position += moveDist; before last }