Hook

Chris Curtis catches Andre Fialho with a right hook

The horizontal curved punch is referred to as the hook.

Basic Mechanics

When throwing the hook, the punching arm should be bent. For a close range hook, the arm forms approximately a 90 degree angle. The angle increases when delivering longer hooks. The bend of the arm does not extend at the end of the punch - fully extending the arm is a common beginner mistake. The forearm of the punching arm should stay roughly parallel to the ground. 

Rotate to the right with the left hook, slightly pivoting off the left foot. As you throw the punch, transfer about 10-20% of your weight from the left foot to the right foot. 

Rotate to the left with the right hook, pivoting on the right foot. Transfer about 10-20% of your weight from the right foot to the left foot. 

Often the lead hook is loaded before it is executed by first throwing a rear hand strike or by simply first using a slipping/bobbing like motion, but this isn't always the case. 

Fist Position

Two fist positions are generally utilized: vertical fist and horizontal fist. Regardless of which you use, you want to try and strike with the first two knuckles of the fist. 

Head Positions

The head positions are generally going to be:

I. Lead Hook

1) Middle 

2) Rear Side 

II. Rear 

1) Middle

2) Lead Side

You can also probably go lead side with the lead hook but I would think it would be used even less than the jab lead side head shift. 

Hooks can also be thrown from lowered versions of the above positions. 

Hook Variations

Hook to the Body

There are various ways body hooks are thrown. Some say that you have to squat down so that you do not leave your head exposed when throwing the punch. Others say that it is a more successful punch when thrown from an upright position and worth the risk. 

Boxing How To Guide - Left Hook to the Body: 

How To Throw Hooks To The Body: Pullmans Gym

*Secret* Tips For Throwing A Perfect Hook To The Body: Tony Jeffries

Why Your Body Hook Might Not Be Awesome....Yet

Changing Levels #6 - Body Hooks & Shovel Punches: Bazooka Joe Vatellini

Curved Step Lead Hook

Used to get you offline at the end of the punch.

*example

Lead Hook with Rear Foot Side Step

*example

Check Hook

The check hook is a hook combined with some sort of evasive footwork used to escape an opponents aggressively moving forward or evade their counter punch. These are generally counter punch techniques so I will likely remove from this section.

1) Front Foot Pivot Check Hook - *example

2) Front Foot Side Step Check Hook *example *example

3) Snap Back & Check Hook

Gazelle/Leaping Hook Punch

A hook punch which uses the gazelle step to cover the distance between you and your opponent. 

How to Throw a Gazelle Knockout Punch

Rocky Marciano's Gazelle Punch Explained - Technique Breakdown