Why do we call it hair on people and fur on animals?

Hair and fur are chemically indistinguishable, having the same chemical composition, and are made of keratin. The primary difference between hair and fur is the word usage. The hair of non-human mammals refers as “fur,” while humans are said to have hair. So, basically, hair is a characteristic of all mammals. Fur is a reference to the hair of animals. But there are a few exceptions: when an animal has very coarse or sparse fur, as in the case of a pig or elephant, we usually call it hair.

In Hebrew, there are seperate words as well.

I’m not sure if they call it the same in other languages but the reason we call it fur on animals is because fur refers to an entire coat of hair that covers the entire body and usually, in most animals, there are several layers of coats to help keep them warm or cool depending on where they live. Also, the texture and consistency of the animal coat is different to human hair.

I’ve actually heard some (non-human) animals referred to as having hair and not fur. I assumed it had something to do with the arrangement or consistency of it.

@incendiary_dan I know some breeds of dogs have hair. The consistency of both are different from each other. I’ve seen both under a microscope and they are different.

As @zen said ..it’s basically the usage of the two words. Hair and fur are the exact same thing. Humans just like to think they’re different than other mammals…go figure.

Human follicles grow a single hair. But many other mammals have several or more hairs per follicle. This is partially why there’s such a difference in the look and feel of different mammal hair (including humans). Another difference can be the oil gland in each follicle. Then the length a “coat” will grow depends on the mammal’s genetic makeup.

Note: Whiskers, quills and even some scaly plates are also hair.

I am unsure of how it is in non-english languages.

Depends on the language. English likes to differentiate the hair on animals from the hair on human beings, because we English speakers like to differentiate ourselves from “other animals”. In other languages, for example Chinese, hair is hair.

Some animals have hair, such as horses.

When it is still on the dog it is fur but when it sticks to your clothing, it is dog hair. I have never heard anyone say, I have dog fur all over my pants!

Some animals are said to be hairy as opposed to be furry.

Hair is usually a longer, coarser material. In some animals with an outer (hairy) coat and a softer (furry or fluffy) undercoat, the undercoat is what provides insulation and warmth while the longer guard hairs repel water and keep the undercoat dry. We humans have mostly lost the undercoat. However, as a handspinner, I can tell you that the undercoat of animals makes a more soft, warm, comfortable yarn and textile product, such as a sweater that you might want to wear. The guard hairs make a tougher, more durable yarn and textile that you wouldn’t want to wear, but is more suitable for things like rugs.

Some animals, such as certain breeds of sheep, have been bred to promote a softer undercoat as all they have left, just like people only have the hair, because it’s a big, labor-intensive pain to sit there separating out the undercoat from the top coat. That’s what you have to do when the fiber has both mixed in it, as happens with some animals (like camel).

In Dutch: Hair = Haar and Fur = Vacht.

Right, as @YARNLADY said.
Horses are one animal that have hair instead of fur.

But, the term is interchangable for many other animals as well.

Cat hair
Dog hair etc.

I would say my cats have fur, but I would then say their ‘hair’ is all over my black chairs. lol

In Norwegian, we say hair (hår) for people but for animals we say ‘pels’. We also use the same word for the furry hide we remove and make coats or what have you out of. We call such animals ‘pelsdyr’ (fur animals), like fox, mink, seal, reindeer, beaver etc…. I think the English word sounds similar for the hides they traded in way back when. They were called ‘pelts’ right? Was that a French word?

One of my lovely nieces had this all worked out when she was about 6 years old. She was adamant that the hair on our heads was hair, but hair on our arms and legs (and anywhere else) was fur and to try to correct her resulted in tears.

The distinction is based on differences in texture and coverage. Fur covers the entire body and is thick. Hair doesn’t cover the whole body, and it is usually thinner and finer than fur.