I think there are two types of hood in the world, two major categories at least: hood, functional, weather (fitted) and hood, snivel (unfitted).
The fitted, functional weather hood
To keep the weather, be it wind, rain, or sun, off my head.
- Drawstrings, side: these run around the front opening of the hood, and allow me to cinch it snugly around my cheeks.
- Drawstring, crown: this allows me to cinch the top of the hood around my head.
- Peak, brim, or visor: this extends the shelter of the hood.
- Weather will only contact the exposed front of my face, as limited by the side drawstrings.
- A peak or brim may help reduce exposure, and reduce the effect of weather being driven into one’s face.
- As I turn my head, the hood will turn with it, not reducing my vision by occluding one eye.
NB: The placement of the side drawstrings is important: if incorrect, they will induce neck fatigue when the hood is correctly adjusted to prevent weather from inducing misery.
The snivel hood
To reduce snivels, be they mental or physical.
- Put hood over head.
- Snivel less.
- Snivelling is reduced.
- Hood will not be adjustable as with the other major category, or if it is, will be limited in its usefulness.
Other possible sub-categories that apply to both major categories
Hood, under helmet
Some hoods are designed to fit under helmets. Based on my experience cycling and climbing (both activities that necessitate wearing a helmet), this is the only type of hood I consider realistic.
Hood, over helmet
A hood worn over the helmet is an annoyance. It will be cut so as to be large enough to fit over the helmet, so that if worn without a helmet will be too large. When not worn, it will flap around loosely, unless it has a chord to cinch it (elastic or ‘shock’ chord). Without this chord, it will catch in any wind, pulling it back off the head.
The only advantage to a hood worn over the helmet is if one needs to quickly recover one’s hearing as almost all hoods compromise the hearing of the wearer. This comes from the noise the hood makes as it moves with one’s head, and from the material occluding the ears.
Some hoods are stowable, either with a pocket they can be tucked into, or a chord that allows them to be compressed down behind the head, or a flap of fabric that is pulled over a rolled up hood to secure it. The latter is annoying, the former full of potential, and the middle the simplest and most reliable.
I consider the Arc’teryx fitted hood (currently on my Gryphon halfshell) to be perfect: while it can be worn over a helmet, it also fits under both my cycling and climbing helmets perfectly. It has a visor and crown adjustment. The side drawstrings do not induce neck fatigue. When I turn my head without a helmet, it turns with me, providing uninterrupted vision. Where they have a stowing option
By comparison, TAD’s hoods are more like bonnets in their style. I have long suspected that the hood on the TAD Stealth and Stealth LT was not tested in a temperate region, as the side drawstrings induce neck fatigue, and the hood does not move with the head: if I want to look to the left, I will lose vision in my left eye. On their fleece and wool jackets, this is much less of an issue, but on the waterproof models it renders the hood only useful if you like looking down and forwards.