How do i make the bullet go in the direction it was fired?

I am new to unity, I cannot figure out how to implement this in my script for bullet.

void update(){     
  float amtToMove = 10 * Time.deltaTime;

This makes the bullet go to the right.
The bullet is instantiated in a different script.
I want the bullet fired by the FPS to move in the direction it was fired. How do i manipulate x and z axis to do that. Thanks in advance.

Firing Script

var myBullet: Transform;  // Bullet Prefab
var shotSpot: Transform;  // Shooting Location 

function Update ()