A brownie/brounie, urisk, brùnaidh, ùruisg, or gruagach (Scottish Gaelic) is a legendary creature in folklore around Scotland and England (especially the north, though more commonly hobs have this role). It is the Scottish and Northern English counterpart of the Scandinavian tomte, the Slavic domovoi and the German Heinzmannchen
The boggart of Yorkshire and the bogle of Scotland are hostile, mischievous brownies indistinguishable from poltergeists.
There is a more violent side to the Brownies than in the Harry Potter house elves, however, and in some Welsh tales, where the Brownies are called Bwca, they have been known to turn on their masters if they suspect that anyone in the household has become a servant of the Devil. Since Bwca, like English Brownies and the Cornish Pixie, are descendants of creatures appointed by Heaven to serve man, they have a strong sense of religious right and wrong. Old tales tell of Bwca slaughtering whole families after learning that the family had become dedicated to evil.
Sadly, some brownies turn bad and become a real nuisance. They overturn churns and spoil the butter, open gates so that the animals can escape, drop nests down kitchen chimneys so that the stoves smoke and won't cook, and generally become as destructive as they were helpful before.
There are different stories about the origin of the name. One is that during the time the Covenanters in Scotland were persecuted because they were said to teach a false and pernicious doctrine, many of them were forced to conceal themselves in caves and secret places, and food was carried to them by friends. One band of Covenanters was led by a little hunchback named Brown, who being small and active could slip out at night with some of the lads and bring in the provisions left by friends in secret places. They dressed themselves in a fantastic manner, and if seen in the dusk of the evening they would be taken for fairies. Those who knew the truth named Brown and his band the "Brownies." We are inclined to believe that the well-deserving hunchback took his name from the "Brownies," instead of the "Brownies" deriving their name from him. Besides the story does not reach back far enough.
They were called "Brownies" on account of their color, which was said to be brown owing to their constant exposure to all kinds of weather, and also because they had brown hair, something which was not common in the country where the "Brownie" was located, as the people generally had red or black hair.
Brownies are always described as being hairy, naked and are attached to one farm or family. They tend to cows and sheep, clean the house, look after the farm buildings, and generally work so that the property or family thrives.
The "Brownie" idea was woven into the affairs of everyday life. In fact it seemed to be part of their religion, and a large part at that. When they churned their milk, or brewed, they poured some milk or wort through a hole in a flat, thin stone called "Brownie's stone." In other cases they poured the offerings in the corner of the room, believing that good would surely come to their homes if "the Brownies" were remembered.
It is said that in the old days, before the Land Clearances, every family had their own Brownie. When they churned their milk a bowl was placed by the back door, when they baked their bannocks a small piece was laid aside, and when they brewed their ale a dribble of wort was poured into a saucer. All of this was done to honour and please the Brownie. For if you had a happy Brownie pleased with your offerings, he would work all night (a great deal of work, the old people said) and lustily clean up your kitchen and shine your hob so that in the morning the sight of the gleaming would dazzle your eyes.
Brownies are good-natured little fellows of the fairy order. They appear only at night to perform kind and helpful deeds and to enjoy a little harmless prank or two while weary households sleep. Brownies never allow themselves to be seen by mortals. For this reason, it is impossible to take a photograph of a Brownie. If you manage to snap off a quick shot of the little chap scrubbing your kitchen table or sweeping the ash from the grate, your camera will cease to function - forever. If you are foolish enough to offend your own household Brownie in this manner, he will leave. And never come back!
In the Harry Potter novels by J.K. Rowling, the "house elves" fit the basic description and character of Brownies.