The bit is one of the primary methods used to establish control and communication. Each one offers variable pressure points, mouth widths, weights and materials designed to prompt different actions and responses from the horse. Whilst some bits are viewed more severe than others, a bit can only be as strong as the rider's hands. The structure of the horse's mouth must also be taken into consideration as this can determine which type is most suitable.

Below is a guide to the various constructions found on bits.

The mouthpiece:

• Thick mouthpieces: Spreads the pressure over a larger surface area, so are deemed milder. However, many horses find the thickness uncomfortable.
• Thin mouthpieces: apply direct pressure to a smaller surface area, offering a quicker response and more control.

Amount of joints:

• The more joints on the mouthpiece, the greater amount of control the bit offers. The exception to this rule is the French link; this is because the linkage in the middle tends to be more comfortable across the tongue than the single jointed bit, which has a nut cracker action.

The material of the mouthpiece:

• Softer materials, or metals, are often more gentle and comfortable in the horses's mouth.
• Harder metals provide more control.

The areas the bit works on the horse:

• Bits with the least amount of pressure points offer less control.
• The more pressure points and areas the bit works on, the more control it will give.

Fixed or moving mouthpiece:

• Fixed mouthpiece: Good for horses who work in a hollow outline, or those with an over-active mouth.
• Moving mouthpiece: For horses who lean, or fix their jaw whilst being ridden.

The length of the shanks or cheeks (pelhams and double bridles):

• Longer shanks apply a quicker action on the curb chain, offering more control than shorter shanks.
• Higher cheeks apply greater pressure on the poll than shorter cheeks.

Curb chains (pelhams, kimblewicks and double bridles):

• Single link (most severe).
• Double link (less severe than a single link).
• Leather curb (mild).
• Elastic curb (mild).
• Rubber covered curb (mild).