Halo: Combat Evolved/Controls
From StrategyWiki, the video game walkthrough and strategy guide wiki
: Used to maneuver your character around the level. Use up and down to move your character forward and backward, respectively. Pressing 
and 
will strafe your character left and right. Push 
to crouch. The character will stand up when the thumbstick is pushed more than halfway along its axis of movement.
: Functions the same as , only you can't crouch. This is useful for precision movements, such as moving exactly forward, or exactly sideways.
: The Back button has no function in Halo Singleplayer. During Multiplayer games, it can be used to review the in-game scores.
: Pauses the game during gameplay. It can also be used in the pre-game GUI to accept the option presented.
: Use to turn your character left and right, as well as aim up or down. By clicking in 
you will zoom whatever weapon you are holding, if it has a scope. The standard zoom is 2X, and 10X with the sniper rifle.
: Use to throw an equipped grenade. Use to change the trajectory. The longest distance to throw the grenade is when you are facing 45 degrees up, and running forward.
: Fire your equipped weapon. It is generally better to pump the trigger rather than hold it down, for the plasma pistol this is true for rate of fire, for the assault rifle this is true for accuracy, and in the case of the pistol, both accuracy and rate of fire are increased.
: Jump while on foot, or brake while in the Warthog, Scorpion or Banshee. The Ghost will lift it's nose if you hold down the button. Run before jumping to go a farther distance. At the height of your jump, press crouch to make your character lift his feet up, allowing you to get up onto higher places.
: Press to initiate a melee attack. If you are low or out of ammo, use this to kill the Covenant. Enemies hit from behind when unaware of your presence die instantly, with the exception of the Hunter. Each weapon has a different range of strike and rate of strike. The fastest is the plasma pistol. All weapons deal the same amount of damage. If you are running while you melee, the hit will do 25% more damage, if you are falling and hit someone on the way down the hit will do 75% more damage, almost enough to kill.
: Your action button. Use to enter/exit vehicles, open doors, etc. It reloads your weapon. It also allows you to exchange your held weapon with one lying on the ground. Automatically refuses to exchange if a plasma weapon on the ground has less charge than the one you are holding.
: Switches your weapon to the holstered one.
: Turns your Flashlight on/off. As the flashlight is turned on, it will slowly drain power. Turn your flashlight off to recharge it.
: Switches your equipped grenades, if you have more than one type. There are only two types of grenades: Plasma and Frag. You can only hold four of each.
