Have you ever played Halo 2 ? If your answer is NO and you are 
interested, then you should read this website.

Introduction

Firstly, you must like shooting games and you have played Halo
in order to understand the story. You will encounter harder-to-kill enemies, new weapons, ride vehicles that you did not get to ride in Halo and a whole new armor which the shield will recharge faster. All this you will learn more later. Here are some pictures: