Hair is dead. There are no nerves in it - as Raiden said, it is only a protein. If you have longish to long hair, try holding it in the middle (so you can't feel it moving) and then touch the ends past that middle, and you can't feel it. When something touches your hair, what you feel is the touch being transmitted to the root, where there are nerves in the skin. So while yes, technically you can feel things with your hair, it's limited to whether someone's touching it, or what the wind is doing

. It also claims that hair 'emits energy', which is clearly false.
Looks like someone has been taking Withnail and I too seriously 
The reason they have long hair is relatively simple: It looks much better, and long and healthy hair has always been a sign of health and a reproductive indicator, which is how humans evolved to be able to grow hair so much longer than other primates in the first place. Indeed, the majority of other humans did too until the early 20th century, particularly the upper classes, and this is returning today

Look at the sidebar links - one is about 'chemtrails' (the vapour caused by the passage of a plane in the right atmospheric conditions). Enough said.
Edit:
This site is hilarious... Believing anything from there means there is no other word than gullible
