Through the first volume of the Harry Potter series, we get lots of interesting and amusing tidbits about dragons. That dragon hide gloves are a required piece of equipment at Hogwarts. That dragon liver fetches a certain price. But the dragons really come alive with the introduction of Norbert.
Now, the common wisdom in Wizarding circles is that dragons are too fierce to ever be tamed. Nevertheless, there’s apparently a recognized trade in dragon eggs. The business is well enough established to provide cover for the wicked Professor Quirrell. Posing as an egg trader, Quirrell tricks Hagrid into telling him about other impressive animals he’s taken care of. Allegedly this is to prove that he can take care of a dragon. In truth, Quirrell wants to know the secret of getting past Hagrid’s guardian beast, Fluffy the three-headed dog.
Even besotted as he is with the idea of owning a dragon, Hagrid knows people aren’t supposed to keep them as pets. He hides the egg, but is found out by Harry, Ron and Hermione. From these passages we learn that baby dragons need a diet of brandy and blood, and that even baby dragons are vicious. Everyone around Norbert seems to get bitten!
Alas for Hagrid, this biting habit led to Norbert being discovered after Ron was poisoned by a bite. (In the movies, it was that sneaky Drako Malfoy who ratted them out.) Dumbledore orders little Norbert sent to one of the dragon reserves, to live among his own kind. In one of the more bizarre Hagrid scenes, our half-giant friend weeps and wonders, “What if the other dragons are mean to him?”
During the remaining books, we get periodic updates on Norbert, courtesy of Ron’s brother Charlie, who is a Dragon Keeper. At last mention, it had been discovered that Norbert was actually a female dragon and had to be re-named Norberta.
Check back next time for a few more dragons who played important roles in the Wizarding World.
Wyrmflight 
Norbert always seemed fairly cuddly, for a dragon.