There are many myths about hair, and sadly perhaps, even hairstylists who should know better circulate some of this hair.

Split ends cannot be repaired and should be cut off immediately or they will split yet higher and do yet more damage.
You already have the micro organism that causes dandruff, yours just aren't as active. On the other hand, there are plenty of nasty things you can get from someone else's comb or brush, so be careful.
To the contrary, brushing your hair is very very very bad for your hair and the leading contributor to split ends and hair breakage. By all means groom your hair, but once it is in place, STOP.
Cancer does not cause hair loss. Hair loss is a side effect of cancer treatments, like chemotherapy and radiation therapy. Not everyone who has chemotherapy or radiation loses their hair either.
A complete myth, wearing a hat has nothing to do with hair loss. However, a lot of people who go bald often wear a hat to hide the fact, something which may account for the origins of this myth.
In contrast to popular belief, going bald is not due to massive amounts of hair falling out, but rather by normal thickness hair gradually being replaced by finer, thinner hairs - a process called 'miniaturization.' If large patches of hair start suddenly falling out, it is time to see your doctor.
A hat fitted too tight can cause hair breakage. And if you don't wash your hat once in a while, it can lead to a dirty scalp. So do yourself a favor and just wash your hat once in a while, and you're gonna be fine.
If you have male pattern baldness, then yes, you'll lose a lot of hair each day. On the other hand, if you don't have male pattern baldness, it can be normal to lose that much hair because it will grow back. Only time will tell, and you should wait and see if it does indeed grow back.
Balding Men should pluck all of their gray hair, as two hairs will grow back in place of each one!
Permanent tints are the only way to cover gray hair - He think everyone can appreciate this one. Depending on the level of gray in the hair it can be ultimately colored with a semi-permanent or demi-permanent - which is not only cheaper, but less harmful to the hair.
Laser hair removal cannot create more hair than you were genetically born with. If this were the case, every bald Canadian man would be fighting to get an appointment for laser hair removal.
Testosterone injections will give you liver cancer. The truth is none of the Testosterone preparations currently used for Testosterone replacement in the United States have any negative effects on the liver.
Grey hair is a different texture than your natural hair. It is courser and more wiry. This means it will not lay down smoothly with the rest of your hair. When you pluck a grey hair it will grow popping straight out of your hair like a little antenna. Your grey hair does become more noticeable but plucking does not promote the growth of other grey hairs.