Orc is Elven for Goblin, and both the pointy eared freaks (as most humans would tern the average elf) and the Dwarves (human terms depend on the last time they did business with a dwarf, and what the outcome was) despise them.
Humans, on the other hand, have developed a complex relationship with them, or perhaps it's the goblins that have developed this relationship.
Goblin kind are ubiquitous denizens of wild lands, and can be feared, despised, tolerated or even treated as something not quite an equal. They are as varied and individually unique as humans are, with the only common features their green tough skin, bowed legs and rather ugly features. They are tough and wiry, and strong for their size, with an amazing constitutional resistance to overexertion and poisons, which may explain their varied and disgusting diet. They have a strange genetic mutability that allows their physical size and other matters to change greatly over only a few generations, something of great use when involved in sustained conflicts, but exploited by warlords and other chaotic leaders with interesting ambitions.
Their social structure is family based, with, depending on the limits of their environment, can be basic family, clan or tribe based. Power is decided by a mixture of the vicious application of both strength and base cunning, with stronger or smarter members preying on, or, even worse, plotting with, those beneath them. Perhaps due to this social pressure, most goblins have cowardice, duplicity and cunning as firmly entrenched moral values.
They live, aside from the rare social outcast, in tribal groups from around one hundred to, in the larger wilderness holdings, over fifty thousand. All with a strong, ruthless leader who directs their innate talents to suitable ends, such as raiding, stealing, infighting or manual labour for chaotic warlords. They are prolific breeders, with the young born in helpless 'litters' of around half a dozen, and about half of these reaching a useful age. Aside from the brief pregnancy, there is no real difference between the sexes, and as no scholar has been desperate enough to investigate, no-one knows or cares anything about the sex life of goblins.
Due to this ready supply of young, the average goblin's life is unimportant to those in charge, as their is always another replacement. The average goblin usually disagrees. But for those who survive long enough, cunning and instinct grow, and exceptional goblins can break away from this cycle and become figures of some importance.
The burrows of goblin clans are varied, but always involve underground caves and tunnels, away from the prying eyes of the sky [Incidentally, in mountain with large flocks of wyvern, goblins can be up to 60% of their diet]. These underground dwellings may be hand dug caves or burrows in earth or soft rock, but they are also known to have taken over habitations from frigid troll caves in high mountain ranges to ruined cities in humid swamps, and most suitable structures in-between.
One must always remember that they are creatures of fey, and can sense hidden magics with great sensitivity, blend into shadow, and use strange powers to misdirect or confuse. As with most fey, it is assumed amongst the greatest naturalists that these were perhaps the original inhabitants of this land, before the Ancients settled and brought in their slave and servant races.
In some of the more tolerant human cities or lands, or those desiring a cheap manual labour force, or those with no-one really in charge, clanless goblins can find acceptance as servants, workers, cleaners, refuse collectors, etc - a general underclass undertaking the thankless and unpleasant duties required where-ever a large group of people settle down. Despite this, usually there is a curfew during daylight hours, where they are required to be outside the city walls in their muddy, refuse strewn shanty town. This does not greatly distress the goblins, as the common warren they sleep in is strangely homelike and comforting.
I've just come across the writings at Huge Ruined Pile, where goblins are addressed, in a much more disturbing manner. I do like, and may steal, the idea of 'upstart' goblins being a
abducted and 'changed' into Bugbears, strange deviants changed with infiltrating other cultures and abducting children that are spirited away to never be seen again...