Medically reviewed by Katelyn Hagerty, FNP
Written by Our Editorial Team
Last updated 5/6/2021
The arguable godfather of the hair typings system used in the world of style and beauty is actually Oprah’s OG hair stylist: a man by the name of Andre Walker.
Walker defined hair textures in the ‘90s with a system of four major categories: straight, wavy, curly, and kinky.
It’s based on two traits: texture and curl pattern. At one end of the spectrum is 1a hair, which is straight and thin, and at the other end, 4b, which is tightly coiled with “z-angle” curls.
Walker’s system is really about directing people to the right practices and products for their hair type (he also produces product lines) but the system isn’t perfect.
Aside from the problems with a system that starts with straight hair as the default, it’s relying on hair texture as the primary organization as opposed to density or coarseness (both of which can be used to describe hair’s “thickness.”)
Density is defined as the number of hairs on your head, whereas coarseness describes the relative thickness of the individual hair follicles.
Still, it also arguably puts the most tools in front of people for communicating hair types.
As we mentioned, Walker’s system is built on four major categories with subcategories to further specify subtypes. As numbers move higher, the texture of the hair becomes less straight; as the letters go higher, the hair becomes more coarse.
Type 1 hair is straight, with a tendency to become shiny or greasy, in part because the oil from your scalp travels down a straight follicle more quickly.
Type 1 hair is divided into three subcategories, 1A, 1B, and 1C. As the letters go higher, the hair gains both volume and thickness, with the individual follicles becoming more coarse.
Type 2 picks up where Type 1 ends: the hair in this category tends to have a subtle wave to it, and tends likewise to be thicker than hair from the previous category.
Type 2 has three subcategories. 2A tends to be more fine, with S-shaped waves, with 2B becoming more frizzy and slightly thicker. 2C is the waviest, and is prone to frizz, which can make it harder to work with.
The difference between wavy and curly is really a spectral one, but Type 3 hair is full of springy curls that are easier to style. It has three subtypes: 3A is shinier, with 3B having tighter curls and 3C having very tight curls.
Type 4 represents the curliest and kinkiest hair, and typically the most coarse texture. Interestingly, while type 4A typically has well-defined curls, 4B and 4C types have such tight curls that it may make the hair appear less curly than some of the earlier hair types in this list.
As we mentioned, this system, while useful, is not an empirical guide to everything you need to know about your hair.
One of the missing pieces of information regards texture. Different textures (described by the thickness of circumference of your hair) can affect how it looks and how it responds to products.
Hair can be likewise categorized in a couple ways: fine or thick/coarse.
Fine hair can be considered thin and fragile, and as we mentioned, it can become greasy or oily more quickly because of its size. Fine hair also breaks more easily than coarse hair, and product can weigh it down.
Coarse or thick hair will always have a medulla layer in addition to the cuticle and cortex, and will always look the most full and thick of the three types.
However, because coarse hair has a thinner cuticle layer, it will also be more prone to breakage.
With coarse hair, you also need to worry about the weather making the problem worse: humid weather can cause frizz and make coarse hair take longer to dry.
There’s also the practical question of what this information is used for.
While your hair’s texture will tell you a lot about how to style and care for it, you’ll benefit just as much from learning about your hair and scalp issues.
Dermatologists will refer you to specific products based on dry scalp, dandruff, oily hair, or whether you’re in need of medication, hydration or thickening (Like what you’ll find in our “Thick Fix” Hair Thickening Shampoo).
Shampoos are made for every kind of hair — remember, some are even designed not to hurt the eyes of babies.
As you might already suspect, all hair types can experience hair loss.
But one fair simple trick to see if you’re losing your hair is to keep an eye on your hair for signs that your follicles are becoming less uniform.
Researchers found that changing hair diameter diversity produced a strong link with something called “follicle miniaturization,” which can be a sign of oncoming male pattern baldness, officially known as androgenic alopecia.
If you see some thinner hairs (wispy is a good way to describe them), you may want to keep an eye out or consult a healthcare professional to see if they’re signs of a larger trend toward miniaturization, which is a flag bearer for oncoming alopecia issues.
Thickening your hair is possible in some cases — read our guide to the Best Hair Thickening Products for Men to find out more.
Whether you’ve learned some new information about your hair or had your previous suspicions confirmed, the good news is this hair information can only benefit you in the future.
But this isn’t everything. Just because your hair fits a type doesn’t mean that dozens of other factors won’t make your own style and maintenance needs unique.
Hair care is less of a flow chart and more of a form of art. It’s about finding what works for you and gives you hair that you can feel proud of.
If you’re learning more about your hair, perhaps because you’re experiencing hair loss, check out our guides to learn more.
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